Short fiction can’t overcome awkward phrasings, careless repetitions, flimsy word choices. There just isn’t enough soil to bury an error. Good editing is about varying approaches and assuming different perspectives.
Read your work in different ways: silently, mouthing the words, pronouncing each syllable, out loud, a little louder, now just a tiny bit louder than that.
Read your work at different times during the day: first thing in the morning when you’re still shaking off the sleep, after a seventh cup of coffee, late at night when you can barely keep your eyes open.
Read your work as another person: someone who hasn’t read a lick of fiction since high school, a surly New York editor with a fat cigar and “REJECTION” stamp, dabbed in red ink, hovering inches above the page.
Edit in different fonts and font sizes. Single-spaced, double-spaced, triple-spaced.
Export to a PDF and let that creepy robot read the work back to you. (Side note: It's a lot of fun to feed the robot dirty words.)
Turn on Track Changes. Sometimes it will push you to take greater risks, rewrite more freely, since it’s so easy to revert back to the original.
When you have the story memorized, can recite it back verbatim, without a mistake, forwards and backwards, standing on your head, then it’s probably all right to start these steps over again.