Cats are generally very good at grooming and keeping themselves clean. If you need to bath your cat for example a flea bath, good luck! But seriously, you can use a treated pet shampoo available at most pet stores.
Tools & chemical:
cat shampoo or medicated flea shampoo, lots of towels and a friend to help.
Try bathing your cat in the kitchen sink, or if that doesn’t work, get right into the bathtub with your cat in your lap be sure you are wearing long pants and sleeves if your cat is likely to claw you!
Note: A smelly cat or dog may indicate that your pet has a health problem. See your vet.