Try to leave out the part that readers tend to skip.
A rule that came to mind in 1983. Think of what you skip reading a novel: thick paragraphs of prose you can see have too many words in them. What the writer is doing, he’s writing, perpetrating hooptedoodle, perhaps taking another shot at the weather, or has gone into the character’s head, and the reader either knows what the guy’s thinking or doesn’t care. I’ll bet you don’t skip dialogue.
My most important rule is one that sums up the 10.
If it sounds like writing, I rewrite it.
Source: New York Times