Screenwriting : Outline by Tejal Desai

DOn't know if this would help you but you could always start with a logline, then expand that out a few sentences, then move on to a paragraph. Then move on to a page. Then 10 pages. Then even 20 pages. By that point you will have a treatment that should be easier to convert into pages.

But if you like working more in the abstract, write out some major beats. Then sequence beats. Then scene beats. Sounds easy, doesn't it?

Are you intending to use a particular structure or would you like to find the structure by working on the story?