Be sure every area in your house has adequate ventilation at all times.
Do not stack boxes or put your furniture flush against a wall, leave space for air to circulate.
Keep the humidity level in your home below 50 %.
Do not carpet bathrooms or other damp locations.
Be sure you have a good bathroom fan that removes moist air.
Leave your bathroom fan on for 20 minutes after showering.
Clean your bathroom with mold/mildew killing products. (household bleach works well)
Use “mold/mildew inhibitors” in paint.
If mildew or mold forms, carefully remove it with full strength bleach and dry the area well.
Dry out, remove or replace any water damaged materials quickly.
Do not turn off your ceiling heat during the rainy months.