Use the screenplay as the outline.

Kick out those slug lines and turn them into sentences.

Present tense? Past tense? First person, third person? You get to decide. But there are pros and cons to each of these decisions. Know what you're getting yourself into before you take a giant leap.

You must elaborate. INT. KITCHEN - DAY isn't going to cut it. You're going to have to describe the kitchen in detail -- is it modern? Rustic? Cluttered? Martha Stewart-esque? How so? Describe it in detail.

You may think you know your characters inside and out, but one of the cardinal rules in screenwriting is to describe the personality and actions of the character and leave appearances to casting. But with a novel, you control the camera. What will your audience see in their mind's eye?

True, with a novel you can delve into what your character is thinking -- but you'll have to establish some rules. Chances are we will know only what your protagonist is thinking because the story will be told through their point of view.

Single POV or multi? Some writers choose to tell one chapter from one character's point of view and another chapter from another character's point of view. Some readers like this, some find it confusing. Decide what you're going to do before you get started.

If you're used to writing television pilots chances are that you've learned to have strong act breaks -- this will prepare you for creating exciting, page-turning books.

Avoid cliff-hangers. Whereas a Netflix audience will watch a cliff hanger ending on an episode and then the next episode will load, readers are more likely to want a satisfying conclusion on the last page.