Start very early in the day.All good thoughts! I definitely have learned there is no one way. I free-range my birds, and love it, though I know others are more protective. As for going slow, out of my 8 hatched chicks, 7 are roosters. (7!!!) Plus, I am hatching Swedish Flower Hens and will likely cull any rooster I can't sell and don't keep for myself. So for my first time culling, I thought I'd make an entire day of it and fill my freezer.
A whole another learning curve is coming my way.
Make sure everything you need is ready at hand. Clean table you can sanitize, running water, a place for the blood, head, feathers, entrails (and do the feathers ever stick to your hands), sharp knives, plastic bags - and practice your workflow a few times.
I think my first bird took me around an hour - defeathering. The first time I disrobed one (skinless), more like 25 minutes. Time has improved on both with practice.
and if there is a good way to get wet, sticky feathers off one's hands and into the desired receptacle without lots of water filling said receptacle, I have yet to find it.
Oh, and wear clothes you aren't fond of - something that washes easily, and takes a bleaching. I like soccer shorts and a shirt of similar materials, and Walmart plastic shoes. Cheap, breathes well, dry quickly - I can step right into the outside shower, clean off, then go back at it or strip down and change into something dry when the job is done.