First thing in the morning, just before they are let out, straight off the perch. They are emtpy then, which helps if you pluck them. Our surplus males (from the home hatched egglayers) just get to the stage where I really cannot bear their crowing and feeding them, if they don't grow anymore..., we normall just skin, take the legs and the (little) breast meat. Good for curries (if marinated o/n) or the Bulgarian Red Wine treatment....
And yes it gets easier and quicker with time, we normally do it together. One holds, the other.... (very sharp axe) very quick, but a bit messy at times.
We also do meatbirds, they of course get plucked etc etc.