Let's discuss the sleeping issue
1. how to fell asleep quickly?
2. how not to fell asleep?

I'm looking forward to your suggestions to question #1, while I can provide several tips for the second one ;-)

1) dont spend the day sitting in front of a computer, be active. Exersise a bit, but dont do so before bed so that your not wired. You will wake up feeling good, and go to bed and fall asleep fast, if your healthy.

2) Dont drink coke before bed

I asked my biology teacher in high school the same question, and his answer was "sex and pot". However, if you're not willing to try those (which are pretty effective), I find that stretching before bed helps me fall asleep.

...I wish i had that biology teacher....Then again, my chemistry teacher would have said the same thing. Heh, once he came into class and he could not spell the word blue.
He walked to the whiteboard and wrote...

Bleu
Belu
Buel
Then said..
"CLASS I CANT FREAKING SPELL BLUE!!"

great tips, Zeitgeist and Charbucks :-)

I remember I wanted to do something important... but I couldn't recall... until now... It was-changing my lifestyle :-)

OK, but imagine I'm staying in a students' college in a small room for two (with a bunk bed). It's in the uppest floor, where the temperature doesn't fall below 30degC before midnight. And my boyfriend has gone abroad..

Well if your extremely active during the day or dealing with alot of personal issues, try clearing your mind first, perhaps read a book, take a bath (even for a guy it can be relaxing), take a walk....

How not to fall asleep, slam your hand in something, the pain will keep you up for a bit im sure...hee hee, just kidding...not sure on that one, usually I try cleaning or listening to music, rock or the sorts, nothing mellow, or better yet, I harass my honey to no end...

Yep doing something to tire your body or mind out will work, but also dont go to bed and lay there, reserve your time in bed only for sleeping for a month or two.
This means if you cant sleep, get up and watch TV, read somewhere, listen to music, anything you can do out of your bed for a while then try sleeping again in an hour or so. This lets your brain adjust to matching the idea of going to bed with sleeping.

Not fall asleep? Do soemthing.

My wife was bothered by insomnia. She has found some relief using tryptophan supplements from the health food store. Tryptophan helps the body in Serotonin and melotonin production. Both are sleep inducing chemicals in the brain. Some studies also see its use as helpful in boosting anti-depressants or eliminating their need in borderline cases.

I find reading helps.

Well, what you should NOT do before going to sleep is puzzling with a programming-task, or problem or anything at all that annoys you! Then you'll just lay there thinking on how it can be solved!

If I need something to clear my mind I usually read a comic or watch cartoons. The simpler, the better

1) I found that when I reduced my caffeine intake a while ago, I slept more deeply and felt refreshed in the mornings, something which never used to happen.

2) As mikeyman said, a hormone called tryptophan causes sleepiness. Turkey contains a high concentration of tryptophan, and it's why some people feel lethargic after consuming turkey.

3) Also, I've found listening to relaxing music helps. Stick a bit of Debussy's Clair de Lune on the stereo, and you'll be asleep in no time.

4) Oh, and good sex before bed is guaranteed to make you sleep peacefully. That might be worth a try too!

I usually find drinking 4 pints of real ale makes me fall asleep quickly.
How not to fall asleep is when there is an illegal rave within 10 miles of your property.

I have no idea how to fall asleep. I agree with Jeremiah, if you don't fall asleep then get up and do something for an hour or so.

As to what I3dx said, I'm pretty much always thinking about something and that's probably where most of my insomnia comes from. I don't know very many ways to turn it off, but I can tell you that thinking about a problem will definitely keep you from sleeping. I guess it's kinda like trying to sleep while running a marathon.