not sure if my last message sent (about contact forms)

Hi. Just a quick and simple request. I am trying to implement a contact 
us form in lenya. Obviously I want to do this using the custom modules 
inbuilt into lenya 2, but I am unsure of how to call it within my page.

I have followed

http://lenya.apache.org/docu20/reference/usecase-framework/usecase-framework-overview.html

however this refers to putting a usecase on the cms. I want it on the 
menubar.

Can I simply call it from a url ie: index.html?lenya.usecase=contact   ? 
or do i need to specify it or declare it anywhere else, and if so where.

If someone could post a step by step guide for this as I really am not 
understaning calling the modules right now :)

Thanks in advance O wise ones

Nick