Page Header on Home Page

Hi there

Really dumb question. I have the premium add ons and I followed the video training on how to make a big picture appear as a page header on my website, merging with the menu etc. I felt very clever to be able to make it work as I'm a technological half-wit.

I have done this on a Page that I set up called "start here".

My question: How do I make this new shiny page header appear on my default home page which isn't a page, it's just a blog roll at the moment?

Thanks and sorry for brain-dead question!
Clare