Before you go diving, it is also important that your mask fits properly (your instructor will assist you). Make sure the mask seal (usually a soft silicone skirt) is free from obstructions, such as hair or your hood. You will also learn how to clear your mask of any water should it leak. It is normal for a little water to drip into your mask from time to time—for instance, when you smile broadly. But if your mask leaks continuously, it probably isn't a correct fit, so try another.