Prerequisites
Download and install WebMatrix beta. This download includes IIS Express (as of this posting, I did not find a standalone download of IIS Express).
Be using Visual Studio 2010 or 2008 and a web project to debug.
Steps to Setup IIS Express
It's actually quite simple to setup IIS express. Once WebMatrix is done installing, go to "My Documents\IISExpress8\config".
Right-click "applicationhost.config" and open in your favorite text editor.
Go to line 145. Notice the <sites> element. This is where we can configure our website for IIS Express. Copy the site that is already there and add another entry below it.
Remove the "autoStart" attribute for the first site.
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