1. Start with the answer, then work back.
2. Name your variables so that anyone will know what they are.
3. Name your functions so that anyone will know what they do.
4. Never write the same line of code twice. Use functions.
5. Assume the user doesn't know what they want.
6. Even if the user knows what they want, assume they can't verbalize it.
7. The user always knows what they don't like. Prototype often.
8. Be prepared to dig down as many levels of detail as needed to understand.
9. When you're stuck, turn off your computer.
10. Don't turn your computer on until you have a specific task.
11. Beauty is important, but delivery is more important.
12. No variable should be fully contained within another variable.
13. All variables should be at least 3 characters long.
14. Use the right tool for the right job.
15. Almost any tool can do the job. Some are better than others.
16. Benchmark often in order to learn what happens under the hood.
17. Try something that's never been done. It may be easier than you thought.
18. Remember the patterns you've used before. You'll use them again.
19. Keep it extremely simple at first. Complexify as you go.
20. Code every day.