Is there any way to get my 11-month-old to sleep more soundly?
Sleep patterns vary greatly from child to child, and there's really no way, to my knowledge, to make your child sleep more soundly. Often, as babies become more active, they will sleep longer and more soundly. Following the same routine when you put your child to bed or when he does awake during the night is the best way to teach him that this is sleep time, not play time. If you need to go in his room, comfort him quietly or rub his back, but try not to stimulate him any more than that. You can keep a few safe toys in his crib that he can play with if he awakens, but you don't need to play with him in the middle of the night.
You might also try some "white noise" outside his room, or at a safe place in his room. This can be a tape of water flowing, a humidifier running, or something similar. Some people, children and adults, sleep better if they hear this background noise. This noise also might prevent him from hearing you coming up the stairs. Good luck!