Do it consistently. I just started rising at 9:30 (this is early for me) every day a few weeks ago, and I now wake up naturally without the alarm, and usually by 9. It only took about four or five days with the alarm and going to bed at a reasonably consistent time (between 1AM and 2AM) every day before I was comfortable waking at this time. I even "slept in" this morning after waking naturally at about 7:30...I rolled over and went back to sleep and got up again at 9:15 feeling pretty well rested. I often take a 20 minute nap between 4 and 6 in the afternoon.

I'm a lifetime overachiever in the field of sleep. If I can convert to a 7-8 hour sleep schedule, anybody can. And I've found that consistency is about the only way I can do it without feeling like crap during the day...so no more all-nighters, no matter how awesome whatever I'm working on is.