My way:

Buy a shitload of weed. Maybe a pound or so.

(this will be in my car)

Put a hose in the exaust, at the other end of the hose, put it in my back window, if there is 2 exaust, then do the same thing.

Start toking up. Smoke as much weed as I can.

Fall asleep, and never wake up.

Carbon Monoxide