I clean mine with a mild shampoo. I give it a good curry first to get the dust out, then fill a bucket with warm water. Dunk the brush to get it wet, then rub some shampoo on (gently!) - mostly just onto the ends of the bristles as the dirt doesn't seem to get very far down anyway. Then rinse well, and hang up to dry. After a quick fluff up, mine's good as new