So you have a shiny new draft! Excellent. You did very well. Now put it in a drawer and leave it alone for at least 2 weeks.
(Two weeks later)
All right, is it ready for prime time? No, probably not. I can help you with some of the technical stuff
Read your manuscript. Out loud. Listen for awkward sentences, repeated words and other things that need fixing.
Second read through:
1) Is this person starting or preparing to do something? Why aren't they just doing it?
2) In scenes with 2 people of the same sex, make sure we know who is talking. Pronoun confusion is real.
3) Check your punctuation. Especially in dialogue.
Correct: “Let's go,” he said.
Incorrect: “Let's go.” He said.
Correct: “Is this right?” she asked
Incorrect: “Is this right,” she asked?
4) Is the adverb necessary? Would a stronger verb suit the sentence?
5) Watch exclamation points. Too many make the reader feel shouted at.
6) Ellipses sound hesitant. A few are fine, but too many make a character indecisive and annoying.
7) Fear of said. Said is a perfectly good dialogue tag. Please do not substitute “enunciated,” “thin-smiled” or “quipped” unless absolutely necessary. Know what your dialogue tags mean.
8) Point of View! If we are in one person's head for all of the scene, keep us there. Do not bounce from person to person.
9) If you are writing an action scene—including a sex scene—do not interrupt it for thoughts. Unless your character is ignoring the action and brooding instead, they should only be focused on the events around them. (Nobody interrupts a firefight for a psychology lesson. Don't interrupt a sex scene for it, either)
10) Watch epithets. The tall man, the short blonde, etc. Names are invisible.
11) Keep your names consistent, especially if you've changed someone's name during writing!
Common bugbears:
Check for these:
A lot, allot and alot. Replace alot with a lot. Allot is a verb
You're (contraction) going to take your (possessive) book home.
They're (contraction) going to take their (possessive) books over there (location).
Two (number) boys are going to (preposition) go, too (also).
It's (contraction) all right, the rain falls in its(possessive) own time.
We can't lose (verb) the goose, even when it gets loose (adjective).
Rein (control, as if with a bridle) in your complaints about it raining (precipitation) on the parade. The Carnival King still reigns (rules over).
Who's (contraction of who is or who has) left this? Whose (possessive) book is it?
Write (verb) down your rites (ritual) so you get them right (correct).
No late papers accepted (taken). No exceptions (exclusions).
Should of, could of. would of. These should be contractions: Should've could've would've
Affect and effect. Most of the time, affect is a verb and effect is a noun. “Let's see if we can affect an effect!” Only in clinical writing is affect a noun.
Then is sequencing. Than is comparison.
Now that you have a manuscript that is technically good, start in on the content edits:
1) Read through your book and take notes. Keep an eye on places you get bored and start skimming.
2) Address the timeline and overall pacing. Easter never comes in MAY! If I had done this step, there wouldn't be dozens of copies of a vampire novel where it did.
3) Round out any flat characters. You created them for a reason. Every character should want something, even if it's just a cup of tea.
4) Fill in gaps in your worldbuilding.
5) Hone your scene-by-scene pacing and dialogue.
6) Copy edit carefully — look out for bad habits! Go back through the list up there.
Always read aloud if you can.
Then comes the fun part of modifying it to house style. If you are submitting somewhere, ALWAYS ALWAYS ALWAYS do their house style. It tells the editor you can follow directions and will probably take edits well. It also shortens their formatter's work.