If I were to commit suicide it would definitely be by burning! But so many self-immolations end with the person being saved and ending up living as a burn cripple, which would be a real reason to commit suicide! If you are going to self-immolate do it away from somewhere you could be "saved", and with more than enough fuel to finish the job. Just to be sure, hand cuff yourself to a post onto of a pile of fire wood to be a pyre, and use lots of fuel!