Ok. So, you've fixed all the big picture problems... right? If not, check out some tips on the big picture edits here.
Now that's sorted, we can look at the smaller details.
(Disclaimer: I am not an editor. These are simply pieces of editing advice I have found to be useful)
5. Scene by Scene
6. Imagery and Metaphor
8. Copy-editing and Proofreading
I hope that you found this helpful, and please remember that this in no way replaces a professional editor.
Until next time: happy editing.