Bathe when dirty or smelly, use pet shampoo, and dry thoroughly to protect skin.

Most dogs do not need weekly baths. Overwashing strips oils and can irritate skin. Cats often need baths only for messes or medical reasons.
Use lukewarm water and pet-formulated shampoo. Protect ears with cotton and rinse until the coat feels clean, not slippery.
Dry fully with towels or a low dryer setting. Damp coats can cause odor and skin problems in skin folds.