I have a hypoallogenic dog shampoo that I use. I fill kitchen sink full enough to just cover their legs and scrub gently as to not damage the feathers. Wet, wash, then rinse. Paying careful attention to feet and bums. Being very careful around face and eyes. Then towel dry or blow dry if it's cold. If it is cold out I have kept them in a cage in the bathroom until they are completely dry. My silkie love loves the blow dryer. Basically, the same way you would bathe a dog just being extra careful to not damage the feathers. Also, I bathe any new birds I get because it gives me a chance to better asses their overall health and check for external parasites. And I use the kitchen sink because it has the sprayer nozzle which comes in extra handy.