Check out my latest Hacks for Hacks column at Writer Unboxed, "Most of the Stuff You Need to Know to Edit Your Manuscript," which is pretty much what it sounds like. You'll find helpful hints like these:
"Trim the fat. Nobody wants to read a flabby manuscript. Take out unnecessary words, as well as all references to fried foods and soda.
Murder your darlings. One of the most useful bits of writing advice, it’s a figure of speech that means that in your novel, you must kill a beloved pet, love interest, or small child. It’s hard, but I didn’t make the rules.
While you’re at it, let some of your minor characters know you might bump off a few of them, too, if they don’t start adding more to the story. Do this out loud."
If you like it, you can read all my columns here.