What you need: A plastic tub or bucket. (dollar tree)
A plastic cup. (save your big gulp cups)
Baby shampoo. (dollar store, generic)
Hair dryer and old toothbrush.
First fill the tub about 1/4 full with warm water and a squirt of baby shampoo. Place chicken in the tub. Keep her head above water!
Wet the chicken completely avoiding her head. You can add some extra shampoo to feet or butts if needed. The chicken may relax. Oh yeah, some chickens think that baths are the ultimate spa experience and they just about fall asleep when placed in the warm soapy water!
If it's cold outside, keep the chicken in the house for a few hours to make sure she's completely dry before you take her back to the coop. That's it!
If nails need clipped, now is a good time to do it. The post Clipping A Chickens Nails will guide you through that process too. Have fun!