Literally something I would never do. First of all, to succeed and die, you gotta jump at least from 40 meters height. Which takes like 6 second of fear and terror that I don't want to experience. 2nd, it's very bloody and messy for those who got families.. The fact that you can survive if landing on legs for example just makes this so not worth it. It's maybe quick and painless. But chances of you dying instantly and not becoming a handicapped person is 50 50. Wouldn't recommend anyone.
For those who got access to weapon, a pistol for example. Just go to a river, lean backwards to the water and shoot yourself in the brain, pointing from inside of your mouth. Then, you'll fall into the water. Which makes this quick, painless and 100% guaranteed. This is what I would recommend.
Or, something that everyone can do but also got balls to accept a good suffering of losing consciousness and not being able to breathe for 30 seconds, hanging is the best one. Doesn't matter if it's full suspension or partial hanging.