Remove all hardware, drawers, and doors
Clean the vanity thoroughly with a degreaser
Sand all surfaces to dull the finish
Fill holes, dents, and cracks with wood filler
Wipe away dust with a tack cloth or damp microfiber cloth
Tape off surrounding areas and protect the floor
Apply a bonding primer suitable for cabinets
Let the primer dry completely
Lightly sand the primed surfaces again
Wipe away dust before painting
Apply the first coat of cabinet paint with a brush, roller, or sprayer
Let the first coat dry fully
Apply a second coat if needed
Allow the paint to cure completely before reassembling
Reinstall the hardware, drawers, and doors
Avoid heavy use and moisture until fully cured