The fact that you cringe when reading your own writing is probably a good thing, because it means you know enough to recognize when something is bad. You'd be surprised how many people can't see the bad in their own writing.

I'd say go through what you have, find part of it that you know needs fixing but you don't know HOW to fix, and post it for feedback. Take the feedback, rework it, and post it again...see if your revisions worked/if there's still more you need to work on.