i think it needs a couple more adjustements before its fully ready but this is pretty much how it will look like. I still feel so bad to use my dog's leash for this. My beloved dog...
You should also practice making yourself pass out by wrapping a rope in criss cross applesauce mode around your neck and pulling the extremities. If you do it right, after about 7 to 10 seconds you will feel dizzy and light headed and you will loose your strenght in your arms which will force you to release the grip, so you dont have to worry about accidents in that case. If your head is filled up with blood and you feel a strong pressure it means that you are choking your jugular which is not efficient, you need to aim for the caroids which are much thicker and resistant, hence you need to have a good technique and to force a bit. Ive trie many times and the best result is when i put the rope just under that Adam's apple, so on the lower part of the neck. Make sure to put some tissue between your neck and the rope so you dont burn your skin. You wouldn't want to have visible marks, would you? :p