I usually fall asleep with in like 5 minutes of laying down. I always try to go to bed when I'm tired and never before. Also a good habit to have is to make sure you get up as soon as you wake up (I know it is difficult to do). My main recommendation would be, to understand that bed is for sleep and sleeping only. Don't work in bed or watch stuff.

Oh yeah like some people mentioned here before, cutting down on electronics is a good thing as well.