This question is not really connected with Sitefinity, but with a common configuration of a Server's IIS. Once you create a web site in the IIS and assign a Sitefinity project to it, it is a matter of setting the web site to answer requests pointed to the http://www.mynewwebsite.com/ domain
. If you have any more questions for creating or working with a project you can refer to the User Manual.
Hope this helps.
the Telerik team
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