Include the following snippet in your html before any other Javascript
<script type="text/javascript" src="http://js.exceptional.io/exceptional.js"></script>
<script type="text/javascript">
Exceptional.setKey('API_KEY_HERE');
</script>
For SSL support use this modified snippet
<script type="text/javascript" src="https://exceptional-js.heroku.com/exceptional.js"></script>
<script type="text/javascript">
Exceptional.setHost('exceptional-api.heroku.com');
Exceptional.setKey('API_KEY_HERE');
</script>