Humidity is often the cause of the frizzies; since there's not much you can do about the weather, use products that contain silicone and try to make the best of it. Still frizzy even when it's not damp outside? You might be handling your hair too much. After you wash your hair, gently squeeze out excess moisture with a towel -- never rub! When you blow-dry, use a round brush (after your hair is partially dried), and be sure to dry your hair completely. During the day, don't brush your hair -- just use a wide-toothed comb when necessary or, better yet, use your fingers. Silicone serum, styling wax or pomade will also help tame the frizz.