The best thing is to have a routine. If you don't have a bedtime. Create one. That should be priority one. The mind will think it's 10:00 (or whatever you choose) it's time to go to sleep.
This may sound a little OCD, but try to do things in the same pattern. The mind will also recognize this pattern and it will get you into the mindstate needed to sleep.
Secondly, are you getting enough sleep? Adults usually need 6-7 hours of sleep at night, some only four. Children need anywhere from 8-12. If you aren't getting enouch sleep sometimes it can cause the reverse effect of sleepiness.
Abstain from caffeene products like pop, coffee, and any kind of stimulant type thing at least three hours prior to sleep.
Also, don't go to bed sleeping in day clothes. This is not only psychosomatic but also allows for you tos leep more comfortably. Again it's also separating in your mind those moments from awake to sleep.
Once you get that down and are still having trouble sleeping...
try counting slowly to 100. Follow your heartbeat. Visualize each number in your head.
Also, listen to calming music before bed. visualize your troubles slipping away with the music. (Calming music doesn't mean classical, whatever calms you down. My friend used to have alanis morrisette playing in the background.)
Since you mentioned crying. Do you write a journal? If not, start one, just a small one, before bed, letting out those exhausted emotions and feelings that have been nagging at you. This way you can close the covers of that book and know that they're in that book now and contained. That's what I do when the anxiety starts taking over my life. Heck, even if you can't write, draw, if you can't draw, do whatever creative medium gets out thouse feelings. That should help, I believe. Make a drawer or something specific for it if it's not in the covers of a book. That way you know it's contained.
) Or just glue your eyes to a screen and then you might get sleepy.
