It's hard and it takes discipline to get the necessary amount of sleep. But you know that your body repairs itself the most during sleep.
I always aim for 8 hours of sleep, but with school and everything, I sometimes only get 6-7, like last night, when I only got 6. However, on days like these, I try to at least get a solid nap in for an hour or so.
In fact, I ALWAYS try to get a nap in, even if I get 8 hours of sleep, even if it is only 30 minutes.
Bulking up takes a lot of hard discipline. You have to eat right, sleep right, and have time for working out. And of course most of us have busy work and school schedules as well. However, if you really want it, you WILL do it. You will sacrifice late night outings because you know you need your sleep for your muscles to repair.
But in the end, you feel better because of it. Missing a couple late night outings is not a big deal...maybe go out once a week instead of 2 or 3. In the end, you will have succeeded and achieved your goal, something that a lot of guys wish for but seldom do.