One thing I have noticed is that the more I worry about not getting to sleep, the longer it takes me to get to sleep - if I manage to get to sleep at all.
I try to trick myself when I'm lying there trying to get to sleep. I tell myself things like, it doesn't matter how much sleep you get tonight because you can sleep in tomorrow (even though I know I have to get up to go to work in the morning). I know it sounds stupid, but it helps.
Remember that even though we may only get a few hours of sleep at night, we're not going to die because of it. Honestly, what's the worst that could happen? We'll just be extra tired the next day not feeling as fabulous as we would if we had gotten a good night's sleep. As many times as we've done that, it should be a piece of cake right? ;p I know it's ridiculously stupid to say so, but try not to worry about it. The more pressure you put on yourself, the harder it is to get to sleep.