One striking image can say more than pages of prose. Remember that.
1) COLOR OUTSIDE OF THE LINES
WRITE IN THE MARGINS as you read your book. But don't read it as you. Read it as your best friend, sister, or co-worker.
Read it through, writing in the margins as you go.
And then, start editing.
JJ Abrams co-wrote a strange book called S:
A young woman picks up a book left behind by a stranger. Inside it are his margin notes, which reveal a reader entranced by the story and by its mysterious author.
She responds with notes of her own, leaving the book for the stranger, and so begins an unlikely conversation that plunges them both into the unknown.
2.) USE THE FORCE, LUKE
Go with your instincts. If a sentence or scene or chapter seems wrong somehow. It is.
Re-write or remove it. Even if it means a major change in your book, do it. Better a Major Change than to have a Major Flop on your hands.
3.) RE-CHARGE THOSE BATTERIES
By the time you’ve written 90,000 words, you can be pretty tired of the storyline, the characters, the plots and subplots, and you’re generally itching to start that new project, too.
So write the first chapter of that new project. It will re-charge your enthusiasm for writing. Mark Twain did that often. Try it.
You will return to editing a new writer.
4.) BE A BULLY -- PICK ON A CHARACTER
Pick a character (other than the protagonist) and follow her or him through all the chapters, seeing if certain phrases repeat ad nauseum about said character.
See if the character remains consistent throughout your novel in manner of speaking, way of handling situations, or way of dressing, etc.
Shift from character to character like that. See if they change slightly from beginning to end.
All real people change somewhat during the course of an adventure. Make sure it happens with each character.
Following one character through your whole novel keeps any character from mysteriously going AWOL without explanation.
5.) BE LOUD ... OUT LOUD
Read each chapter aloud after the written edits. You will catch misfires in rhythm and flow that way. Think listener. Would he or she be bored, waiting for something good to happen?
Like Elmore Leonard said: "Leave out the boring stuff!"
6.) PYRAMID SCHEME YOUR BOOK
Take one chapter at a time to edit. Polish that chapter. Make it flow and shine -- then go on to the next.
A neat trick is to edit your first chapter and then edit your last one, striving for a symmetry of images, a Before and After bookend effect.
7.) EAGLE EYE VIEW
Your book is a whole. Your final edit should shape it into a coherent, consistent whole. Put your novel on a diet if you must. Weed out those needless flowery phrases that slow the flow.
No long paragraphs to tire the reader's eyes. Alternate types of sentences. Want to craft a scene of action? Short sentences with words denoting the tone of the scene.
8.) MAKE YOU SENTENCES BREATHE.
Each scene of action should be introduced with a pensive scene so that the reader will be caught off guard.
The action scene should not end predictably, but with a twist that floors the action into even more danger for your heroes.
9.) EDITING IS LIKE PEELING AN ONION
With each layer completed you cry a bit, and then you go on. But eventually, you stop or you run out of onion.
Do not edit the life out of your novel. Keep it fresh by stopping for a few days, doing something else you love, and then go back to it.
Remember why you thought your novel would be such a good thing that you committed to it. Limit yourself to three full edits. If you can, try for only two.
Remember that test when you kept changing the answer to that troublesome question? Odds are, your first answer was the right one. So I end with ...
10.) TRUST YOUR ABILITY.
You are not aiming for the PERFECT novel but one that ENTERTAINS your reader. Keep it fun.