I've actually blogged about this list before, but didn't know its provenance (or have the full quota) until I came across an entry on it via the excellent LISTS OF NOTE:

Late-1979, New York Times columnist William Safire compiled a list of "Fumblerules of Grammar" — rules of writing, all of which are humorously self-contradictory — and published them in his popular column, "On Language." Those 36 fumblerules can be seen below, along with another 18 that later featured in Safire's book, Fumblerules: A Lighthearted Guide to Grammar and Good Usage.

Trivia: Safire previously worked as a speechwriter and was, in 1969, responsible for penning Nixon's thankfully unused and incredibly chilling, "IN EVENT OF MOON DISASTER" speech.

(Source: Maximum Awesome; Image: William Safire in 1968, courtesy ofNYTimes.)

1. Remember to never split an infinitive.
2. A preposition is something never to end a sentence with.
3. The passive voice should never be used.
4. Avoid run-on sentences they are hard to read.
5. Don't use no double negatives.
6. Use the semicolon properly, always use it where it is appropriate; and never where it isn't.
7. Reserve the apostrophe for it's proper use and omit it when its not needed.
8. Do not put statements in the negative form.
9. Verbs has to agree with their subjects.
10. No sentence fragments.
11. Proofread carefully to see if you words out.
12. Avoid commas, that are not necessary.
13. If you reread your work, you can find on rereading a great deal of repetition can be avoided by rereading and editing.
14. A writer must not shift your point of view.
15. Eschew dialect, irregardless.
16. And don't start a sentence with a conjunction.
17. Don't overuse exclamation marks!!!
18. Place pronouns as close as possible, especially in long sentences, as of 10 or more words, to their antecedents.
19. Hyphenate between sy-llables and avoid un-necessary hyphens.
20. Write all adverbial forms correct.
21. Don't use contractions in formal writing.
22. Writing carefully, dangling participles must be avoided.
23. It is incumbent on us to avoid archaisms.
24. If any word is improper at the end of a sentence, a linking verb is.
25. Steer clear of incorrect forms of verbs that have snuck in the language.
26. Take the bull by the hand and avoid mixing metaphors.
27. Avoid trendy locutions that sound flaky.
28. Never, ever use repetitive redundancies.
29. Everyone should be careful to use a singular pronoun with singular nouns in their writing.
30. If I've told you once, I've told you a thousand times, resist hyperbole.
31. Also, avoid awkward or affected alliteration.
32. Don't string too many prepositional phrases together unless you are walking through the valley of the shadow of death.
33. Always pick on the correct idiom.
34. "Avoid overuse of 'quotation "marks."'"
35. The adverb always follows the verb.
36. Last but not least, avoid cliches like the plague; They're old hat; seek viable alternatives.
37. Never use a long word when a diminutive one will do.
38. Employ the vernacular.
39. Eschew ampersands & abbreviations, etc.
40. Parenthetical remarks (however relevant) are unnecessary.
41. Contractions aren't necessary.
42. Foreign words and phrases are not apropos.
43. One should never generalize.
44. Eliminate quotations. As Ralph Waldo Emerson said, "I hate quotations. Tell me what you know."
45. Comparisons are as bad as cliches.
46. Don't be redundant; don't use more words than necessary; it's highly superfluous.
47. Be more or less specific.
48. Understatement is always best.
49. One-word sentences? Eliminate.
50. Analogies in writing are like feathers on a snake.
51. Go around the barn at high noon to avoid colloquialisms.
52. Who needs rhetorical questions?
53. Exaggeration is a billion times worse than understatement.
54. capitalize every sentence and remember always end it with a point