need help making a multipost page

I created a my diary page and i would like to make it a multipost page, however it will only allow me one post, and i tried to create a page using my diary as a parent page, but then when i try and navigate on the main menu, it loops the paths, can anyone tell me how to make the my diary page a multipost page, in addition to my main page, which is multipost? do i need another plug in?

Any advice would be appreciated thanks
Jo
http://www.wannabenormal.com