I've always thought hanging was the best way to do yourself for a number of reasons. One consideration wold be that it's a lot nicer for the EMT's compared to someone blowing their brains out. Maybe not so much in this case!
While you wouldn't want to be found too soon, giving someone the chance to cut you down and try and revive you, it might be nice to make sure you would be found by the next morning at least. Maybe leave a note in your mailbox or something.