Smoke a cigarette without breathing between puffs....Make sure you inhale all of it. It will make you "sleepy". Make sure it's a high CO cigarette, it's usually written on the side how many mg. And smoke as fast as possible. Don't smoke it slowly. You will feel like you're gonna faint, get dizzy etc...
I use it as a quick acting "sleeping pill"...usually takes two to three cigarettes or less depending on how fast you smoke.
Once you get the fainting/dizziness feeling, it's hard to get up etc...So you just go to sleep...