First rule: remember your reader has a short attention span. Write for that reader in short powerful sentences.
Go back and edit and edit again. Make it shorter, tighter. Be positive, not negative – that’s a Hemingway rule.
Hemingway told F. Scott Fitzgerald in 1934 “I write one page of masterpiece to ninety-one pages of shit. I try to put the shit in the wastebasket.”
Right now my wastebasket is full. Is yours?