Turn off the water supply to the tap
Plug the sink drain to prevent losing small parts
Open the tap handle and remove the decorative cap if present
Unscrew and remove the handle
Remove the retaining nut or cartridge cover
Take out the cartridge, stem, washer, or O-ring
Inspect all seals, washers, and O-rings for wear or damage
Replace any worn or damaged parts with matching new ones
Clean mineral buildup from the tap components
Reassemble the tap in the reverse order
Tighten all parts securely, but do not overtighten
Turn the water supply back on
Test the tap for leaks
Replace the entire tap if the leak continues or parts are unavailable