I used to be a night owl. Recently I started commuting in at 5:30 AM ... I get to work by 6:00 and can leave at 2:30, and spend the rest of the afternoon with my kids, or doing stuff during daylight hours (as opposed to formerly working 9am-5:30pm)

For me, I try to be as passive as possible for the hour or so before bed. Read or work on the computer and listen to the radio. The other thing that really helps me is a routine. I make my lunch for the next day, set out a bowl of cereal for the next morning, clothes, etc. If you have a routine then your body, eventually, will pick up on the hints and figure out that bed comes next.

Finally, do it every day of the week - don't sleep in weekends. Yeah, this can suck, but it's also nice to have a few quiet hours in the morning. Take a ride or do something fun. But if you get in the cycle of 5 days on, 2 days off (or whatever) that first day back on is very hard and a hit to your body.

Good luck!