How do I redirect a link using php or javascript with a Content Gateway?

Hi,

I need some help. I want the gateway to show up when some one click on the link.

<a href="#download" onClick="javascript:initGateway();return false;">Click here</a>

Code (markup):

here is my gateway code:

<!-- Interstitial :: Start -->
<script type="text/javascript" src="http://interstitial.powered-by.pinballpublishernetwork.com/fd2fed27b5ce840faea85789afda85b039d9"></script>
<!-- Interstitial :: End -->

Code (markup):

How should the code be written?
Please help,

Thanks in advance.