There is a 'humane killer' which looks a bit like a pair of pliers, you use it just below the head from behind, close them up and it dilocates the neck, much easier then 'pulling' an older cockerel, tho I still go through that motion to seperate it more. (have to psyche myself up for about a week before, seeing it as a roast instead of a pet
). I also have a short piece of lead pipe handy 'for emergencies'
I'm sure its a deed we all hate doing, but I prefer to do it rather than put them through the stress of a market, I've watched the way they are handled and it's not nice.