Now that's something I have yet to do- I have wanted to give a few a bath but didn't know if they would like the idea. Was it easy? Did they seem to like it or no? With all the extra dark soil and red clay here I think I shall get the black ones.
Let's just say there is no way in hell I would give my alpha roo, a large fowl ameraucana, a bath. The small ones already kick and scream and hate it. Add his size, weight, spurs, and the fact that a mere flapping of his wing has broken a nose... and there's just no way!
I kinda have to do it with silkies, because they just seem to COLLECT mud in their feathers! But they are much smaller, and don't cause bruising or bad scratches!
When I do it, I use lukewarm water, and a cat flea and tick shampoo (it helps with mite problems, and enough will rinse away to be safe). And I use a VERY generous amount of soap, because somehow, only a tiny fraction ends up on the bird. The rest ends up on the ceiling, walls, and in my own hair, before ever getting close to the chicken.
Pretty sure my head is permanently free of fleas and ticks now!
And I use the kitchen sink because it has the sprayer so I can rinse their belly without flipping them upside down. But that's pretty redundant, since they'll flip themselves upside down a few times as they realize there is nothing to grab in a sink to get away....
.... except you.
And try as best as you can to keep most of your body away from them as you bathe them. No, not for the drench factor, since you will end up wetter than the chicken no matter what you do. But rather because a chicken trying to climb out of water with no grip on their feet WILL try to pull themselves out using their mouth and neck muscles.
Oh, and make sure you actually LET GO of the button on the sink sprayer when it gets kicked. Then again, you'll probably need that extra water flying across the room to rinse off the soap that made it there first!