Gather the drain kit, plumber’s putty or silicone, wrench, screwdriver, and rags
Remove the old drain, if present
Clean the drain opening and surrounding surface
Apply plumber’s putty or silicone under the drain flange
Insert the drain flange into the tub opening
From below, attach the drain body and gasket
Tighten the drain assembly securely
Install the overflow plate and gasket, if included
Connect the overflow pipe to the drain assembly
Tighten all connections
Wipe away excess putty or silicone
Fill the tub with water and check for leaks
Tighten or reseal any leaking connections
Reinstall the drain stopper or strainer