20. Ask someone else to proofread.
I think that even as an editor, this is a good tip. Sometimes, your eyes have a way of playing tricks on you especially when you’re reading something over and over again. I would suggest having an avid reader or someone knowledgeable about punctuation, grammar, syntax, etc. look over your work before you send it to your editor for final review. This way, you are able to work any necessary kinks out. The editing process is very tedious, but it is so worth it!