Turn off the water supply to the bathtub
Plug the drain to prevent losing small parts
Remove the faucet handle
Take off the escutcheon or trim plate
Inspect the cartridge, stem, or valve assembly
Replace worn washers, O-rings, or seals
Replace the cartridge or stem if damaged
Clean mineral buildup from faucet parts
Apply plumber’s grease to moving parts
Reassemble the faucet
Turn the water back on
Test for leaks
Tighten any loose connections if needed
Replace the entire faucet assembly if repairs do not stop the leak