How does early bedtime for an infant get started?

I have a three month old, my second child. I can hardly remember the experience with my first, but we didn't get him on a regular schedule until about 5 months, and with a lot of crying it out. My three month old goes to bed around 10:30pm, but I read online and my friends report putting their three month old babies to bed at 6:30! How does that happen? My son is wide awake no matter what I do, bath, feed, rock, etc. And if he does sleep before 10:30 he usually wakes up again soon. What does "putting him to bed" really mean? I can put him in his crib early after soothing and feeding, but that doesn't mean he sleeps!