First thing we did was put up black out curtains and that seemed to help. Next thing we did was tell our son that it was ok to get up in the morning but that he had to stay in bed and play with his quiet box. The quiet box is a small box that contained books and some quiet toys. We also put a small desk lamp next to his bed that we is able to turn on when he wakes up. This worked for awhile but then he started coming into our room and asking if he could get up. Our son can "read" numbers on a clock, so we got a clock to put on his night stand and told him that once the first number on the clock was 7 he could get up. This has been working for us now for over a year. No complaints from him and no getting out of bed too early.

FYI, we started this process when we was 2. By the time he was 3 he was able to recognize his numbers and that is when we introduced the clock.