how do you kill them?
Cats I choke out with a catch pole they die very quickly, the rest I shoot. I believe these two methods are as humanly as you can possibly be when dispatching them.
I'm not one to use a knock in the head because it causes a mess when you clean them.
PETA don't care how you kill them they don't like any method. If you notice the mangy one, this is from overpopulation. They would rather they all die like this and suffer greatly than be managed and used as a resource.