Last month I attended a revision workshop hosted by SCBWI Germany/Austria. They brought in Sara Grant (co-founder of Undiscovered Voices and editor at Working Partners), and her Revision Game workshop was FABULOUS! I learned a ton.
I can't share everything Sara taught us, but here are a few snippets to get you started.
Figure out what's at the heart of your story. What's the meaning behind it? (What point were you trying to make? Why did you write it?) Now read your story with this in mind. Did you tell the story you wanted to tell? No? Revise accordingly. Get rid of anything that doesn't get at the heart of the story.
Create a time line. You probably wrote over weeks, months, or even years, and it's easy to lose track of the day of the week/time of day in the story. Is the timing consistent?
Check for duplications, action (too much? not enough?), exposition (too much? not enough?), dialogue, and setting. Make sure your readers know where the scene takes place and who is talking, but don't overuse attributions.
Read the story for each character (read only that character's scenes). Can you track the character's emotional arc? Do you even need this character? If not, can you combine it with another underused character to make one stronger/more relevant character?
Once you've got the big stuff figured out, it's time for micro-editing.
(If you're a member of SCBWI, see if you can get your region to host a workshop. Sara lives in the UK, but her debut novel Dark Parties comes out in the US in August, so she might be in the neighborhood if you're state-side. Seriously, look into it. I can't recommend it highly enough.)
What do you do first when you start to revise?