Those that can't write ... read about it.
My current project seems to be stalled at the moment. Not writer's block, just too much else (computer work) going on to concentrate. So I've taken up Hitch's recommendation (well, reminder, it has been on my list of some time) and started reading
"Self-Editing for Fiction Writers" by Renni Browne and Dave King (2nd edition).
I'm impressed. There is not a lot in there that I have not read before, in one form or another, but here the concepts are presented together very clearly with examples and exercises.
(The cartoons aren't very effective for me, in the paperback edition I purchased some of them are barely legible, but you can't have everything.) While little of it is completely new, they do identify some important distinctions that you rarely see mentioned elsewhere (eg: adverbs that are props for your dialogue versus those that modify the verb "said", as in "he said softly"). I find these distinctions really help to make the concepts clearer, because you get to see what is bad about the poor choices as a contrast against those things that (in their proper place) may actually add value.
One thing I particularly like is that they make it clear early on that these aren't hard rules. They're guidelines, things to watch out for and try to balance. Which isn't to say that some things are not strongly recommended, but there is little of the unwarranted exaggeration you see on so many blogs and articles around the 'net.
And one aspect that I did not really expect: it's remarkably easy to read. I've only been at it for a day and I'm already two-thirds through. No, I'm not working my way through all the exercises this time around, I expect to be reading it again (and again ...), especially now that I've found it such an easy read and one that I can relate to very well.
Reading about it not going to make you good at it, you have to practice, which is where their exercises come in. But, even after that, having a reference like this to remind you of what to look for when reviewing your own work has got to be a good thing. It is an entirely practical and effective guide.
Not that the authors of this book need it (they have so many other endorsements), but I heartily recommend this to all aspiring writers. You should have this book!
Note: This is a book about self-editing, concentrating mostly on copy-editing rather than structural editing. There is some discussion of point-of-view, proportion and voice, and I tend to think of these as structural editing decisions even though the correction of mistakes in these areas often takes place during copy-editing. This is not a book about spelling, grammar or proof-reading. We have discussed tricks to help with proof-reading here on MR before.
I have a 300 page second draft sitting here waiting for me, so I have something to practise on ... just as soon as those people who pay me stop harassing me for more work. (Please don't tell them I said that, as inconvenient as work can be, it's nice not going hungry.) Or maybe I've got enough head space for editing, even if I don't have it for writing. It's worth a shot.
Disclaimer (for HarryT

): Just because this book can help you to self-edit does not mean you can avoid a professional editor. The better you can make your work before it goes to the editor the more effective your editor can be. And, the better you understand the concepts the more easily you can understand what your editor is trying to tell you.