It is important to care for your quality woollen hat properly. When it comes time to wash your hat make sure you wash it in luke warm water as cold or hot will shock the fibres and they will react adversely. Hand wash in luke warm water with a wool detergent like Softly or even hair shampoo. Hand wash twice and then rinse twice. To remove all the water spin dry on woollen cycle in washing machine or roll in a towel and kneel on roll to remove water. Lay flat to dry in the shade. A piece of elastic can be threaded through the band as the hat wears and stretches to keep it firmly in place.