Clear the sink area and place a towel or bucket under the drain
Look for a pivot rod nut under the sink and loosen it by hand or with pliers
Disconnect the pivot rod from the drain stopper linkage
Lift the stopper straight up from the sink drain
If it is a push-pull stopper, twist it counterclockwise and pull it out
If it is stuck, wiggle it gently while lifting
Remove any hair or debris from the stopper and drain opening
Reconnect the pivot rod if needed after removal
Tighten any loosened parts back into place
Test the stopper to make sure it moves freely