Fix the moisture source first
Repair leaks in pipes, walls, windows, and foundation
Improve drainage around the home
Use a dehumidifier to keep humidity below 50%
Increase ventilation in the basement
Remove and discard moldy porous materials
Clean non-porous surfaces with detergent and water
Use a mold-killing solution on affected hard surfaces
Scrub visible mold thoroughly
Dry all cleaned areas completely
Replace damaged drywall, insulation, or carpeting
Seal cracks and gaps after drying and repairs
Wear gloves, goggles, and an N95 mask during cleanup
Bag and dispose of contaminated materials properly
Call a professional if mold covers a large area or keeps returning