From the great George Orwell comes some solid writing advice.
1. "What am I trying to say?"
2. "What words express it?"
3. "What image or idiom will make it clearer?"
4. "Is the image fresh enough to have any effect?"
5. "Could I put it more simply?"
6. "Have I written anything unavoidably ugly?"
These questions should apply to every sentence you write to stand a chance of being published in the traditional manner. The lesson I learned during my creative writing course = writing is much harder than it looks.