Revision.

Synopsis of a good book, titled Revision, by David Michael Kaplan.

The steps of revision:

• Revise before you write: make guesstimates of your plot, find out what it is that’s valuable, and try to find ways to revise your ideas of plot based on where you think you’re going to go. I.e., don’t just start writing with your first idea.
• Revise while writing your first draft: first drafts don’t have to be in any particular order (unless you’re posting as you write). Think of a scene you missed? Write it, add notes as to where it should go, move on. Can’t figure out how to write a scene? Skip it. Make whatever notes you think you’ll need and go on. Don’t feel guilty about it. Change your mind about adding or removing a character, etc.? Just do it, and don’t worry about how you’re going to add or remove the character–just write as if it had always been done. Don’t back up and rewrite. Revising means changing your vision of the story. Rewriting means a waste of time during the first draft.
  

Now you’ve written your first draft.

• Revise for meaning: decide what it is that your story’s about. Is it about love? Is it about fathers? Is it about aliens with cucumbers being driven into the universe by their cruel masters? The first thing you should do is decide what’s important.
• Revise for a weak opening: Delayed openings, overly detailed/repetitious openings, unnecessary history/background openings, and unnecessary flashbacks.
• Cut what’s not essential: philosophic ramble, repetitions, tangents, useless amplifications, dreams, stagey dialogue (the kind where the dialogue tells you an unnatural amount of backstory), unnecessary characters and events.
• Add what’s essential. Something’s missing when: characters don’t talk or talk indirectly, characters don’t do anything, ghost characters (characters not described), scenes in limbo (scenes not described), characters without thoughts, missing crucial scenes (or crucial scenes described indirectly), “tell” scenes that need to be “show” scenes, full scenes used for things that could be done as transition or bridge scenes.
• Rearranging plot: check for scenes that are chronologically out of order, psychologically out of order (make sure the character really would feel A before doing B), dramatically out of order (generally moving the most important items to the end of the series to build tension), putting complex dramatic shifts into a clear order, elements that are out of order in terms of meaning (an old flame that appears when a couple is having doubts, rather than an old flame that appears after everything is resolved).
• Revising endings: Make your endings “unexpected, but believable.” Don’t use message endings, deus ex machina endings, trick endings, smoky (unresolved) endings, confusing endings, or unearned endings.

Finally, save the prose for last.