Configuring Sites for a Specific Runtime Wizard
When you configure your site you have the option to choose any Visualforce page as the Active Site Home page. However, a case may exist in which you would prefer for the site to take the user directly to a runtime wizard, rather than giving the user the option to choose it from Wizard tab home page. In this case you will have to configure a URL Redirect for the site.
To set up a URL redirect: