For now, try this:
Write without stopping to worry, correct, or edit. A way to better writing is practice. A way to practice is to start writing and to keep writing for more than five minutes without stopping. You will write some phrases you will really love. You will find it hard to throw them away.
Be ready to to throw them away because they probably won't fit the writing you end up with. If you don't come up with a whole new focus or angle, you will probably come up with a whole new subject.
Before you do throw away what have written do this: Read it and pick out your best three or four best sentences. Then reread them. As you do so consider improvements you might make in them. Rewrite them and save them for a while.
Richard Sheehan