Hang yourself, drink bleach, suckstart a gun, run into traffic, run in front of a train, jump off a building, cut one of your arteries, mix barbituates with alcohol(don't fucking do this it's painful as fuck), drown yourself, electrocute yourself, overdose on drugs, carbon monoxide yourself(best way), set yourself on fire.
There are millions of ways to do it. People that do, don't post on the fucking internet about it first.