Foot Wash Tap leakage mainly caused by its wear-out Valve.

Please follow the steps below to replace the Valve.

 Valve

Take out the small cover.

Sometimes, a paper-cutter knife can help you easily to take out the cover.

Screw out the screw.

Turn out the handle.

Screw out the valve and replace with a new one.   

Then assemble the foot wash tap.

Counterclockwise  to loose  the valve.

Clockwise  to fix/fasten  the valve.