well, turn off your lights and make sure your room is really dark. Then start counting from one to infinity. If that doesn't work, imagine you're in some place else and make your own story in your head. If that also doesn't work, listen to calming/ soothing music. If all else fails, you're just not ready to sleep, just go back to DML and or watch a really really boring drama. and i'm sure once you're bored, you'll fall asleep