Beginning with blurbs
If you don't have a premise already, use this one: Why did the protagonist fake those maps?
Write a back-cover blurb for that story, making it up as you go along: make the blurb completely over-the-top, camped-up marketing-style stuff, as cheesy as you like; a pastiche of blurb-writing; have fun with it. Write as many blurbs as you want. Write that first, then scroll below the pictures.
Using your blurb, start writing the first scene of the novel: prick the reader's curiosity, and keep half an eye on the main plot drive you're headed for and the set-up you want to weave in.
For more on Beginnings, you can download Story Elements: The Complete Set - only available until 30 December 2014. Find out more, see previews, and download it here.
Tomorrow, we're writing with... symbols.