I voted jumping because that's personally my main method for CTB. I know that it is a very risky method since there's too many variables like height, how fast you're falling, how you land, the flatness and density of the surface etc. However I got a strange fixation about it that I can't really explain, it's kinda symbolic in a way. I have some few spots in mind that should do the trick.
Hanging would be my second option since it's the cleanest method of them all to my knowledge, plus it's pretty surefire to go rather quickly when you do FSH.
Firearms is possibly the fastest method out there if you got the means to get one, however it's very messy and the success rate of an instant death is highly dependant on where you aim and the ballistics of the caliber.
SN seems like a good contender too, but to my understanding from browsing this site, you seem to need a lot of other kinds of medication and detailed prep work in order to achieve a peaceful sleep. Rawdogging it just sounds painful.
Opiates like oxycodone/heroin/fentanyl seem like a good option since opiates make you feel numb and euphoric, but if you're unlucky with a low dosage you might be semi conscious when you begin to stop breathing (however if you do enough you'll be so high it won't really be an issue, most likely you'll stop breathing in your sleep). Plus personally I only have access to oxycontin (40mg) and they're pretty hard to come by.
Exit bag is a method I'm too unfamiliar with, so I can't give a comment about that one.
