Delilah S. Dawson recently wrote a great post about leveling up your writing. Aside from the geek points she gets for using the term “level up,” the list has lots of great info for new and not-so-new authors alike. My favorites are “kill dialogue tags” and “kill adverbs,” both of which I find I need to do when rewriting.
I should mention that, too–gather as much writing advice as you can. Learn it by applying it. But never, ever let advice kill your mojo. If you worry too much about doing it “right,” you run the risk of not doing it at all, and that’s way worse than doing it “wrong.”