Hello my fellow anons, I'll get straight to the point. I want to kill myself with helium. I want to put my head in a bag, fill it with helium and die peacefully. I don't want to hear any blah blah talk about how I shouldn't do it and how life is good, I've already made up my mind. Anyway, I need some advice. I've already purchased helium, but I'm not sure what kind of bag should i buy. I'm also not sure exactly how to make sure it doesn't accidentally let air in. I need it to work on the first try. Any advice?

Also sorry for my English :)