If your custom web form looks like this after embedding it on your website, it is most likely conflicting with the CSS style sheet on the webpage you are using. 

To resolve this, copy and paste the highlighted code into your webpage editor, before and after your web form EMBED code, as shown below: 

<center><style type="text/css">

div.wizard input[type="text"] {display:inline-block;}

div.wizard {line-height:normal;}

div.wizard input {padding:2px;}

</style>

<div class="wizard">

<!-- START EMBED CODE -->

THIS IS WHERE YOUR WEB FORM EMBED CODE WILL BE

<!-- END EMBED CODE -->

</div></center>

<center><style type="text/css">
div.wizard input[type="text"] {display:inline-block;}
div.wizard {line-height:normal;}
div.wizard input {padding:2px;}
</style>
<div class="wizard">

<!-- START EMBED CODE -->
THIS IS WHERE YOUR WEB FORM EMBED CODE WILL BE
<!-- END EMBED CODE -->

</div></center>