In the industry there are three phases of editing and it’s an idea to replicate that in your own editing practice.
Structural edit
This is the overall edit. Is the structure firm? Is the ending satisfying? Do the characters work? Are they consistent? Are they balanced? Are they speaking the right way? Does the setting work? Is any world you’ve created consistent? Is time behaving? Is there a good narrative balance? Is there pace and tension? Are there times where the reader can relax a little?
Line edit or copy edit
Look again at narrative balance. Are you telling where you should be showing? And do you occasionally need to tell instead of showing? Have you used too many clichés? But remember clichés are clichés because they work. Have you used an even voice throughout? Can you get rid of any bits that are too clever? (Kill off your darlings – that old cliché). Are you repeating yourself? Can you find some alternatives for words you are using a lot? Check to see that you’re not overwriting. Can anything be more succinctly expressed? Look out for awkward phrasing. Have you got the right combination of shorter and longer sentences? Check your paragraph length. Reading aloud can help here. You’ll more easily notice what isn’t working.
Proof read
This is where you look for typos and grammatical, spelling and punctuation mistakes. Could you read your work backwards? Reading aloud may also help here. It’s useful to get another pair of eyes on your work. Swap proof-reading with a writing friend.
If you are self-publishing you might seriously consider paying professional editors and proof-readers.
Extra tip 1
Put your work away for a while between edits.
Extra tip 2
Write yourself a checklist based on the above. Also include the mistakes you always make and devote one edit to that. My example: I often type ‘form’ instead of ‘from’.
Extra tip 3
Change font and formatting for each edit. It makes you see the text better.
Extra tip 4
Start each edit at a different part of the text.
Find more tip sheets here