Turn off the water supply to the sink
Open the faucet to drain remaining water
Disconnect the supply lines
Disconnect the drain trap and drain assembly
Remove the sink, countertop, and backsplash if attached
Cut any caulk along the vanity edges
Remove screws or fasteners securing the vanity to the wall
Pull the old vanity away from the wall
Inspect and repair the wall, floor, and plumbing as needed
Measure and mark the placement of the new vanity
Install a new shutoff valve or plumbing modifications if needed
Move the new vanity into position
Level the vanity with shims
Secure the vanity to wall studs
Install the countertop and sink if separate
Reconnect the drain assembly
Reconnect the water supply lines
Apply caulk along edges and seams
Turn on the water supply
Check for leaks
Seal any gaps and clean the area