Turn off the water
Put on gloves
Identify the drain plug type
Lift and twist the stopper if it is a toe-touch or lift-and-turn type
Unscrew the stopper counterclockwise if it is a threaded type
Remove the overflow plate screws if it is a trip-lever type
Pull out the linkage attached to the trip-lever stopper
Use pliers or a drain key if the stopper is stuck
Turn the stopper counterclockwise while lifting gently
Remove any visible hair or debris from the drain opening
Clean the drain threads and stopper before reinstalling
Keep the removed parts together for reassembly