The #1 reason for sleep deprivation is stress. If something is bothering you then minute amounts of adrenaline are secreted in your bloodstream. It's akin to drinking a pot of strong coffee before bedtime. The only real solution is to practice the concept of acceptance. You need to accept the things you cannot change,have the courage to change the things you can. And have the wisdom to know the difference. Accept life and human nature as it is,and you will sleep better.
Most of the time it is for me, especially if I have alot on my mind. I just try to relax or focus on listening to music to sleep.
If you wake up in the middle of the night,don't worry about it as it is perfectly normal. This is known as "bimodal sleep". The average person will wake up 1 or 2 times a night. Usually we will fall back to sleep within a few seconds or a minute at the most. Some people however can't get back to sleep and will lay there for 45-60 minutes. This problem can be solved by getting up and taking a melatonin tablet. Melatonin is the natural substance released into the bloodstream by the brain with the onset of darkness,to make us fall asleep. Melatonin is harmless and there are no side effects with taking it. Give it a try if you are having sleeping problems........Sweet dreams.
Thinking to much before sleeping can cause you to stay awake. Clear your mind and just relax. Therefore do not worry about tomorrow, for tomorrow will worry about itself. Each day has enough trouble of its own.
For those with problems, I suggest trying brownian noise: en.wikipedia.org/wiki/Brownian_noise I personally use a fan at pretty much all times of the year, and it helps me quite a bit. If you don't want to use a fan though, something like simplynoise.com might work.