For draft writers, you don't have to do these revisions in order but here's a start. That's looking at your characters to make sure they're fully developed. Characters are what makes a reader want to continue writing. Part of a writer's job is to mane the characters appealing whether they be heros, heroines or villains. Even those characters who have a small role unless they're walk-ons need to have something to draw the reader to them.
For me developing a character means becoming the character. This can sometimes cause people to look at you strangely, especially when you're walking not in your own shoes but those of the character. What are some of the points to consider. This will be an overview today and in weeks to come will look at specifics.
Completeness - this doesn't mean putting in every event in the character's life but in giving the reader enough information to make the character come to life.
Believability -- this means that the character acts in ways that go along with their personalities and not doing things that seem to be out of character.
Consistency - there's nothing more disturbing that a character who constantly shifts from acting one way in a situation and a totally different way in a similar same situation.
Distinctiveness -- this looks at individuality and at what makes your character different from the hundred other characters who may be facing a similar story.
Function in the story -- what is the character's role and does he fulfill it or skirt around the edges. This is particularly important for secondary characters.
Stereotype -- unless you really need a cardboard character in the book making a character look like a cookie-cut one will make the reader yawn.
So during the rewriting phase making characters vivid and real is important.