I have to read to get to sleep at night but if I still can't sleep I do the following and it really does work. Well it does for me anyway....
Take yourself off to bed and try to relax your muscles all over. Then, starting with your feet only, tense up, hold it for a few seconds and then let go. Move on to your ankles only and do the same then on to your calves, knees, thighs... Keep doing this. slowly moving up your body a bit at a time, all the way up to your head and then down your upper arms, elbows, lower arms, then hands and finish with your fingers.
Someone told me about doing this years ago and, despite being very cynical about it, I gave it a go and was surprised that within a few minutes of doing it I did actually fall asleep. It seems to work for me every time. It's got to be worth a try for you. I did have to do it twice the first time I tried it though.