Step 1

First, you should insert styles for the Demo pop-up. They will look like the below (click on arrow):

    <style>
      #signupModal .modal-body {
        background: white url('http://www.fabl.co/assets/img/accounts/fabl/modal-signup-5ecf122652.jpg') no-repeat 100% 100%;
        padding: 8% 9%;
      }
      #signupModal .modal-header {
        padding: 0px !important;
        background-color: white;
      }
      
      @media (min-width: 768px) {
        #signupModal .modal-dialog {
          width: 800px !important;
        }
      }
      
      .fabl-promotion h6 {
        text-align: left !important;
        font-size: 1rem !important;
        line-height: 1.2 !important;
        margin-top: 0 !important;
        margin-bottom: .75rem !important;
        opacity: .4 !important;
        text-transform: uppercase !important;
        font-weight: 700 !important;
        letter-spacing: .05em !important;
      }
      .fabl-promotion h3 {
        font-family: 'adobe-garamond-pro', 'Adobe Garamond', Garamond, serif;
        letter-spacing: 0 !important;
        text-align: left !important;
        text-transform: none !important;
        font-weight: normal !important;
        font-size: 2rem !important;
        line-height: 1.25 !important;
      }
      .modal-content a.modal-close {
        font-size: 45px !important;
        color: #222 !important;
        transform: rotate(45deg) !important;
        width: 24px !important;
        height: 24px !important;
        display: block !important;
        position: absolute !important;
        top: 30px !important;
        right: 30px !important;
        cursor: pointer !important;
        z-index: 999 !important;
      }
      .modal-content a.modal-close:hover {
        text-decoration: none !important;
      }
      
      .modal-body .form-combo {
        background: #eee !important;
      }
      .form-combo {
        display: block !important;
        background: rgba(0, 0, 0, 0.05);
        box-shadow: none !important;
        border-radius: 4px !important;
        font-size: 17px !important;
        height: 2.5rem !important;
        padding: .5rem 1rem !important;
        line-height: 1.5 !important;
        color: inherit !important;
        outline: none !important;
        margin: .5em 0 !important;
        border: 1px solid transparent;
        padding: 0 !important;
        display: table !important;
        width: 100% !important;
      }
      .form-combo > * {
        padding: .5rem 1rem !important;
        display: table-cell !important;
        background: transparent !important;
        border-width: 0 !important;
        box-shadow: none !important;
        margin: 0 !important;
        white-space: nowrap !important;
      }
      
      .form-combo > *:last-child {
          text-align: right;
      }
      
      .grid .grid-6 {
          width: 50%;
          padding: 0 4px;
          display: inline-block;
          vertical-align: top;
          box-sizing: border-box;
      }
      
      .fabl-promotion .offer {
          font-size: 17px;
      }
    </style>
    

Step 2

Copy and paste this code snippet that includes the form itself, script for sending the request, and script for minor customization of the form behavior:

<div id="demoModalContainer">
  <div class="modal fade" id="signupModal" tabindex="-1" role="dialog" aria-labelledby="demoModalLabel">
    <div class="modal-dialog">
      <div class="modal-content">
        <div class="modal-header">
          <a class="modal-close pull-right" data-dismiss="modal" aria-label="Close">+</a>
        </div>
        <div class="modal-body">
          <div class="fabl-promotion">
            <h6>Elevate Your Story</h6>
            <h3>Register for a Fabl Demo</h3>
            <form name="signupForm">
              <div class="grid">
                <div class="grid-6">
                  <div class="form-combo">
                    <label for="first_name">First Name:</label>
                    <input type="text" name="first_name" id="first_name" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="last_name">Last Name:</label>
                    <input type="text" name="last_name" id="last_name" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="email">Email:</label>
                    <input type="email" name="email" id="email" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="phone_number">Phone:</label>
                    <input type="text" name="phone_number" id="phone_number" class="form-control">
                  </div>
                </div><div class="grid-6">
                  <div class="form-combo">
                    <label for="company_name">Company Name:</label>
                    <input type="text" name="company_name" id="company_name" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="website">Company URL:</label>
                    <input type="url" name="website" id="website" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="title">Position:</label>
                    <input type="text" name="title" id="title" class="form-control">
                  </div>
                </div>
                <div class="grid">
                  <div class="grid-6">
                    <input type="submit" class="btn btn-primary btn-med btn-block" value="Let's Do This">
                  </div>
                </div>
              </div>
            </form>
          </div>
        </div>
      </div>
    </div>
  </div>
</div>

<link href="https://fabl.co/assets/components/growl-3038ae10f84bc8e0/stylesheets/jquery.growl.css" rel="stylesheet" type="text/css" />
<script src="https://fabl.co/assets/components/growl-3038ae10f84bc8e0/javascripts/jquery.growl.js" type="text/javascript"></script>

<script type="text/javascript">
  $(function () {

  
  // Handle form submit
  // ---------------------------

  var $modal = $("#signupModal");
  var $form = $("form", $modal);
  $form.on('submit', function(e) { //use on if jQuery 1.7+
    e.preventDefault();  //prevent form from submitting
    var data = { registration: {}};
    $.each($form.serializeArray(), function(_, kv) {
      data.registration[kv.name] = kv.value;
    });
    $.ajax({
      type: "POST",
      url: "https://api.fabl.co/api/registrations",
      dataType: "json",
      success: function () {
        $modal.modal('hide');
        $form[0].reset();
        $.growl.notice({ title: "Thank you for signing up! ",  message: "We will be in touch with you shortly." });
      },
      error: function () {
        $.growl.warning({ title: "Something goes wrong.",  message: "Sorry, we were unable to record your contact information at this time." });
      },
      data: data
    });
  });

  if (window.location.search.match(/request-demo/)) {
    $('.signup .btn.btn-primary.btn-med').click();
  }
});
</script>

<script type="text/javascript">
jQuery(function ($) {

  var jqCookiesUrl = "https://cdnjs.cloudflare.com/ajax/libs/jquery-cookie/1.4.1/jquery.cookie.min.js";
  var bsUrl = "https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js";

  loadScripts([bsUrl, jqCookiesUrl], function () {
    console.log("Load Scripts!");

    var $modal = $('#signupModal');
        
    setTimeout(function(){
      $modal.modal('show');
    },2000);
    
    $('#signupModal .modal-close').click(function(){
      $modal.modal('hide');
    })

  });
});

</script>
    

Note: This form will be shown after 2 seconds. To change this time period, you should go to setTimout(... , 2000) from ‘2000’ to whatever you need.

To see what the form looks like, simply click the button.

(Optional - Variant 1) Create an inline form

To set up this form as inline, you should copy the code snippet below

<div id="demoContainer">
  <div id="signup" tabindex="-1" role="dialog">
    <div class="dialog">
      <div class="content">
        <div class="header"></div>
        <div class="body">
          <div class="fabl-promotion">
            <div class="fabl-promotion-legend">
              <h4>GET ACCESS TO A FABL DEMO & MORE!</h4>
              <p><span class="demo-form-alert">*</span> indicates required</p>
            </div>
            <form name="signupForm">
              <div class="grid">
                <div class="grid-6">
                  <div class="form-combo">
                    <label for="first_name">First Name:<span class="demo-form-alert">*</span></label>
                    <input type="text" name="first_name" id="first_name" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="last_name">Last Name:<span class="demo-form-alert">*</span></label>
                    <input type="text" name="last_name" id="last_name" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="email">Email:<span class="demo-form-alert">*</span></label>
                    <input type="email" name="email" id="email" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="phone_number">Phone:</label>
                    <input type="text" name="phone_number" id="phone_number" class="form-control">
                  </div>
                </div><div class="grid-6">
                  <div class="form-combo">
                    <label for="company_name">Company Name:<span class="demo-form-alert">*</span></label>
                    <input type="text" name="company_name" id="company_name" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="website">Company URL:<span class="demo-form-alert">*</span></label>
                    <input type="url" name="website" id="website" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="title">Position:</label>
                    <input type="text" name="title" id="title" class="form-control">
                  </div>
                </div>
                <div class="grid">
                  <div class="grid-6">
                    <input type="submit" class="btn btn-primary btn-med btn-block" value="Let's Do This">
                  </div>
                </div>
              </div>
            </form>
          </div>
        </div>
      </div>
    </div>
  </div>
</div>


<style>
#signup .body {
  background: white url('http://www.fabl.co/assets/img/accounts/fabl/modal-signup-5ecf122652.jpg') no-repeat 100% 100%;
  padding: 8% 9%;
}
#signup .header {
  padding: 0px !important;
  background-color: white;
}

@media (min-width: 768px) {
  #signup .dialog {
    width: 800px !important;
  }
}

.fabl-promotion-legend h4 {
  display: inline-block;
  clear: both;
  width: 100%;
  <!--font-family: 'adobe-garamond-pro', 'Adobe Garamond', Garamond, serif;-->
  letter-spacing: 0 !important;
  text-align: center !important;
  text-transform: none !important;
  font-weight: normal !important;
  font-size: 1.5rem !important;
}


.fabl-promotion-legend p {
  font-size: 14px;
  text-align: right;
}
span.demo-form-alert {
  color: red;
}

.body .form-combo {
  background: #eee !important;
}
.form-combo {
  display: block !important;
  background: rgba(0, 0, 0, 0.05);
  box-shadow: none !important;
  border-radius: 4px !important;
  font-size: 17px !important;
  height: 2.5rem !important;
  padding: .5rem 1rem !important;
  line-height: 1.5 !important;
  color: inherit !important;
  outline: none !important;
  margin: .5em 0 !important;
  border: 1px solid transparent;
  padding: 0 !important;
  display: table !important;
  width: 100% !important;
}
.form-combo > * {
  padding: .5rem 1rem !important;
  display: table-cell !important;
  background: transparent !important;
  border-width: 0 !important;
  box-shadow: none !important;
  margin: 0 !important;
  white-space: nowrap !important;
}

.form-combo > *:last-child {
    text-align: right;
}

.grid .grid-6 {
    width: 50%;
    padding: 0 4px;
    display: inline-block;
    vertical-align: top;
    box-sizing: border-box;
}

.fabl-promotion .offer {
    font-size: 17px;
}

</style>

<link href="https://fabl.co/assets/components/growl-3038ae10f84bc8e0/stylesheets/jquery.growl.css" rel="stylesheet" type="text/css" />
<script src="https://fabl.co/assets/components/growl-3038ae10f84bc8e0/javascripts/jquery.growl.js" type="text/javascript"></script>

<script type="text/javascript">
  $(function () {

  
  // Handle form submit
  // ---------------------------

  var $modal = $("#signup");
  var $form = $("form", $modal);
  $form.on('submit', function(e) { //use on if jQuery 1.7+
    e.preventDefault();  //prevent form from submitting
    var data = { registration: {}};
    $.each($form.serializeArray(), function(_, kv) {
      data.registration[kv.name] = kv.value;
    });
    $.ajax({
      type: "POST",
      url: "https://api.fabl.co/api/registrations",
      dataType: "json",
      success: function () {
        $form[0].reset();
        $.growl.notice({ title: "Thank you!",  message: "We will be in touch with you shortly." });
      },
      error: function () {
        $.growl.warning({ title: "Something goes wrong.",  message: "Sorry, we were unable to record your contact information at this time." });
      },
      data: data
    });
  });

  if (window.location.search.match(/request-demo/)) {
    $('.signup .btn.btn-primary.btn-med').click();
  }
});
</script>

(Optional - Variant 2) Create an inline form

To set up this form as inline, you should copy the code snippet below

<link href="https://fabl.co/assets/components/growl-3038ae10f84bc8e0/stylesheets/jquery.growl.css" rel="stylesheet" type="text/css" />
<script src="https://fabl.co/assets/components/growl-3038ae10f84bc8e0/javascripts/jquery.growl.js" type="text/javascript"></script>

<script type="text/javascript">
  $(function () {

  
  // Handle form submit
  // ---------------------------

  var $modal = $("#signup-simplified");
  var $form = $("form", $modal);
  $form.on('submit', function(e) { 
    e.preventDefault();  
    var data = { registration: {}};
    $.each($form.serializeArray(), function(_, kv) {
      data.registration[kv.name] = kv.value;
    });
    $.ajax({
      type: "POST",
      url: "https://api.fabl.co/api/registrations",
      dataType: "json",
      success: function () {
        $form[0].reset();
        $.growl.notice({ title: "Thank you!",  message: "We will be in touch with you shortly." });
      },
      error: function () {
        $.growl.warning({ title: "Something goes wrong.",  message: "Sorry, we were unable to record your contact information at this time." });
      },
      data: data
    });
  });

  //if (window.location.search.match(/request-demo/)) {
    //$('.signup .btn.btn-primary.btn-med').click();
  //}
});
</script>

<div id="demoContainer">
  <div id="signup-simplified" tabindex="-1" role="dialog">
    <div class="dialog">
      <div class="content">
        <div class="header"></div>
        <div class="body">
          <div class="fabl-promotion">
            <div class="fabl-promotion-legend">
              <h4>GET ACCESS TO A FABL DEMO & MORE!</h4>
              <p><span class="demo-form-alert">*</span> indicates required</p>
            </div>
            <form name="signupForm">
              <div class="grid">
                <div class="grid-6">
                  <div class="form-combo">
                    <label for="first_name">First Name:<span class="demo-form-alert">*</span></label>
                    <input type="text" name="first_name" id="first_name" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="last_name">Last Name:<span class="demo-form-alert">*</span></label>
                    <input type="text" name="last_name" id="last_name" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="email">Email:<span class="demo-form-alert">*</span></label>
                    <input type="email" name="email" id="email" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="phone_number">Phone:</label>
                    <input type="text" name="phone_number" id="phone_number" class="form-control">
                  </div>
                  <div class="form-combo">
                    <label for="company_name">Company Name:<span class="demo-form-alert">*</span></label>
                    <input type="text" name="company_name" id="company_name" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="website">Company URL:<span class="demo-form-alert">*</span></label>
                    <input type="url" name="website" id="website" class="form-control" required="">
                  </div>
                  <div class="form-combo">
                    <label for="title">Position:</label>
                    <input type="text" name="title" id="title" class="form-control">
                  </div>
                </div>
                <div class="grid">
                  <div class="grid-6">
                    <input type="submit" class="btn btn-primary btn-med btn-block" value="Let's Do This">
                  </div>
                </div>
              </div>
            </form>
          </div>
        </div>
      </div>
    </div>
  </div>
</div>


<style>
#signup-simplified .body {
  padding: 8% 9%;
}
#signup-simplified .header {
  padding: 0px !important;
  background-color: white;
}

@media (min-width: 768px) {
  #signup-simplified .dialog {
    width: 800px !important;
  }
}

#signup-simplified .fabl-promotion-legend h4 {
  display: inline-block;
  clear: both;
  width: 100%;
  <!--font-family: 'adobe-garamond-pro', 'Adobe Garamond', Garamond, serif;-->
  letter-spacing: 0 !important;
  text-align: center !important;
  text-transform: none !important;
  font-weight: normal !important;
  font-size: 1.5rem !important;
}


#signup-simplified .fabl-promotion-legend p {
  font-size: 14px;
  text-align: right;
}
#signup-simplified span.demo-form-alert {
  color: red;
}

#signup-simplified .body .form-combo {
  background: #eee !important;
}
#signup-simplified .form-combo {
  display: block !important;
  background: rgba(0, 0, 0, 0.05);
  box-shadow: none !important;
  border-radius: 4px !important;
  font-size: 17px !important;
  height: 2.5rem !important;
  padding: .5rem 1rem !important;
  line-height: 1.5 !important;
  color: inherit !important;
  outline: none !important;
  margin: .5em 0 !important;
  border: 1px solid transparent;
  padding: 0 !important;
  display: table !important;
  width: 100% !important;
}
#signup-simplified .form-combo > * {
  padding: .5rem 1rem !important;
  display: table-cell !important;
  background: transparent !important;
  border-width: 0 !important;
  box-shadow: none !important;
  margin: 0 !important;
  white-space: nowrap !important;
}

#signup-simplified .form-combo > *:last-child {
    text-align: right;
}

#signup-simplified .grid .grid-6 {
    width: 100%;
    padding: 0 4px;
    display: inline-block;
    vertical-align: top;
    box-sizing: border-box;
}
#signup-simplified input[type="submit"] {
    width: auto;
    margin: 0 auto;
}
#signup-simplified .fabl-promotion .offer {
    font-size: 17px;
}

</style>