Calcium is supposed to mellow you out and help you sleep, and Calcium's companion, Magnesium does the same. Take both, or one or the other at bedtime with a little milk ( too much milk and you will need to get up and pee).
Like cs, I read at night, and a boring book will put me to sleep in no time. I prefer introductions, they're very boring.
When I wake up during the night I make sure to change position, which takes a bit of work, and then I think about what I'm going to wear the next day. For some reason that is the most sleep inducing thought, and I usually fall asleep before I've made any decision. It is also so inane and so neutral a line of thought that it doesn't give me bad dreams.
A comfortable bed that is not used for daytime napping is a big help.
This subject is really not one into which I have deep insight, so my advice is not worth anything to those with real sleep problems. I sleep well. I don't often sleep more that 5 - 6 hours at night, but for a PWPD that is a good, long night's sleep. I don't take sleeping pills, I hope I never need to, but I can understand the desperation that makes one give in after long periods of sleeplessness.