When I do it it will be by a high impact method as that seems the most foolproof. Either jumping or going to a stretch of highway where there's no other motorists to endanger, and driving at high speed into a tree or pole.
My method used to be a plan to step in front of a train but I've seen terrible videos of people being cut in half and remaining conscious and alive for whole minutes while people stood around gawping and filming.
Even jumping isn't necessarily foolproof I know, and you have the total consciousness before you hit the ground. I very recently saw a video on Reddit of a jumper who, and this feels like a chance in a million, landed on one of those upright columns that block off people from parking their cars. It impaled him through the anus and came out of his shoulder. He lived long enough that medics were able to get him off the pole and to hospital and he died later that day.
I don't want my death to be a humiliating agonising spectacle that gets shared in troll subreddits and Facebook groups for months.