Hi. I currently run a site called prizepwr (prizepwr.com)

I am redesigning the site completely but i have hit a bump in my work.

I need to implement some code of signup.php (a registration file)
This is what it looks like once its running.

But i want to insert it into the XML file/page below
(excuse the request quote button)

Is there any way i can achieve this or insert the XML into the PHP?
If you need to look at the code of any files just tell me.