Fix the moisture source first
Turn off HVAC if mold is widespread
Wear gloves, goggles, and an N95 or respirator
Open windows and improve ventilation
Seal off the work area
Remove and discard heavily mold-damaged drywall
Lightly mist the area to reduce dust before removal
Cut out affected drywall with a utility knife
Bag contaminated drywall and debris immediately
Clean remaining framing and surfaces with detergent and water
Scrub visible mold from non-porous surfaces
Dry the area completely with fans and dehumidifiers
Apply an EPA-registered mold cleaner if appropriate
Replace removed drywall only after the area is fully dry
Prime and paint with mold-resistant products
Monitor for recurring moisture or mold growth
Call a professional if the mold covers a large area or keeps returning