Four secrets of bathing cats:
1. Close the bathroom door behind you and the cat.
2. Run the tub full of water before putting the cat in it, and have a plastic dish nearby. A sopping wet cat is a demoralized cat. A half-wet cat will fight to the death to avoid becoming a sopping wet cat. Drop cat into tub, and use the plastic dish to ladle more water over him until he is sopping wet.
3. Either clip claws BEFORE you start, or put a thick towel in the tub, so the kitty will dig his claws into the towel. With any luck, his claws will stick, which diminishes his ability to wriggle, and keeps him from getting a paw loose to claw YOU.
4. If it's cool weather, towel dry your cat, then pop him into a carrier. Use a 1960s era soft bonnet hair dryer (the kind that stretched to go over curlers) to finish drying kitty: put the bonnet over the door, and turn it on. It's much quieter and the air flow is lighter, so it doesn't frighten a cat like a modern blow dryer does. It just fills the carrier with warm soothing air, and keeps kitty warm as he dries (rather than having him hide under the furniture in a draft.)