how do you butcher a chicken

first of all, i love this website. ive been reading many many posts and learned a lot about raising chicken.
i currently have four english banty hens. they are pretty young now, but when do they get old, we plan to butcher them. i havent butchered an animal in my life but i have seen others do it and it doesnt look all that complicated... however, i understand that it involves a lot of planning and knowledge and i dont want to screw up! i have nobody around to show me how its done. i went on youtube and seen some videos. i want it as humanely as possible. thanks for any feedback.