Remove everything from under the sink
Place a towel or bucket under the drain area
Locate the pivot rod connected to the drain pipe
Loosen the retaining nut on the pivot rod
Pull the pivot rod out of the drain assembly
Lift the stopper straight up out of the sink drain
If the stopper has a visible cap, unscrew or lift it off first
If the stopper is stuck, twist it gently while pulling upward
Clean any debris from the drain opening
Reinstall the pivot rod and tighten the nut if needed