I agree with the tips and suggestions (esp. about routines), but also want to add my experieneces.
Some kids just don't sleep as much as others.
My son never slept for more than 2 or 3 hours at a time until he was well over 6 months old. As a newborn he was excruciating - he'd nurse for an hour, and then WOULD NOT SLEEP. Instead, he would want to be held and be in motion for about an hour and then be ready to nurse again and then NO SLEEP, *must be held with motion*.... He knew what he wanted
As a toddler, he would *maybe* have a 1 hour nap in the afternoon. His bed time was 7:30 pm and he would wake up at about 4:30 am.
He stopped napping daily when he was about 2 1/2.
He never slept past 6am until he was over 5 years old.
He is now almost 8 years old. He "goes to bed" at about 8:30 (after bath and story) and likes to read in bed until almost 9pm (ocassionally even later). He usually wakes up (without an alarm clock) between 6am and 6:20 am. Never naps.
My daughter, by contrast slept through the night when she was about 6 or 7 months old and took regular naps until she was 3. She goes to bed at the same time as my son, but she would easilly sleep past 7:30 am if we let her.