What you should do is inventory your resources. What type of narcotics and/or benzodiaprenes do you have to work with? Do you have any without acetaminophen in them because it is toxic to use too often. Alcohol by itself is a neurological depressant. If you consume a lot of it, chances are you will pass out but you probably won't like the way you feel when you wake up. Occasionally, some people don't wake up. Chloroform is dangerous to play with because it has dangerous side effects and it is too easy to overdose. Thats why it is used only as a solvent.
After you determine what your resources are, take the time to learn about them. Some are safer than others. Some work differently than others. You don't want to take something that knocks you out and stops you from breathing. That might be a bad thing. Also, don't experiment unless someone is there to monitor you. They should not try the drug when you do. They need to be able to respond if there is a problem.
The best way to learn how to do it is by working with someone who has experience. If they have been out a few times and aren't dead, they probably have good information. I won't tell you specifically what to try because this is a public forum with too many impressionable minds. Also, be careful who you believe. Don't put your life in the hands of a total stranger.