Insert this into the <head> of your web site.
<script src='https://cdn.goodforms.com/verify.js'></script>
Invoke the constructor with your API key -
Goodforms('fk_your_form_key')
This should activate email verification for your website - any field with a name of 'email', or a type of 'email', or an id of 'email', will automatically verify, with default visual effects and behavior.