try having a hot bath and hot cocoa before bed, write down everything on your mind especially things you need to remember like things to do the next day etc so you do not have to subconciously try and keep them in your mind, make sure your bed is warm and comfy, relax with scented candles and calming music rather than TV, do not eat or use the computer for two hours before or whilst in bed as this stimulates the brain, so does coffee, tea, coke/cola, cheese. get into a relaxing bed time routine and stick to going to bed at the same time, turn out the light and close your eyes, it may take a few nights of this taking hours before you fall asleep before you start to find yourself falling asleep earlier and earlier until your brain sees the light going out as a trigger to sleep.

hope this helps good luck x