The following rules have been around on the Internet for a long time. If anyone can provide me with an attribution, I will gladly credit the author(s).
1. Avoid alliteration always.2. Prepositions are not words to end sentences with.
3. Employ the vernacular.
4. Avoid cliches like the plague (they're old hat).
5. Eschew ampersands & abbreviations, etc.
6. Parenthetical remarks (however relevant) are unnecessary.
7. It is wrong to ever split an infinitive.
8. Contractions aren't necessary.
9. Foreign words and phrases are not apropos.
10. All generalizations are bad.
11. Eliminate quotations. As R W Emerson once said: "I hate quotations."
12. Comparisons are as bad as cliches.
13. Don't be redundant; don't use more words than necessary.
14. Who needs rhetorical questions?
15. Be specific, more or less.
16. Exaggeration is a billion times worse than understatement.
17. One-word sentences? Eliminate.
18. Analogies in writing are like feathers on a snake.
19. The passive voice is to be avoided.
20. Go around the barn at high noon to avoid colloquialisms.
21. Even if a mixed metaphor sings, it should be derailed.