"A scrupulous writer, in every sentence he writes, will ask himself at least four questions, thus:
1.What am I trying to say?
2.What words will express it?
3.What image or idiom will make it clearer?
4.Is this image fresh enough to have an effect?
And he will probably ask himself two more:
Could I put it more shortly?
Have I said anything that is avoidable ugly?