If there’s dampness in the basement run a dehumidifier. Yes, that includes new, tightly constructed homes.
Do not open basement windows – moist warm outside air will condense with the cool basement air.
Don’t store anything on the basement floor, especially paper products. Elevate stored items on metal or plastic shelves to for allow air circulation. Store papers and cloth in plastic bins with tight lids.
Keep gutters and downspouts clean. Divert rainwater away from the house.