Turn socks inside out. Machine wash on gentle cycle in warm or cool water.Turn socks inside out. Machine wash on gentle cycle in warm or cool water (avoid hot water as heat may shrink wool). Use mild soap, no bleach or fabric softener (bleach destroys the Merino wool fibers, and fabric softener coats those fibers—reducing their ability to naturally manage moisture and regulate body temperature). While you can tumble-dry most of our Merino, we recommend air-drying to reduce your environmental impact and further extend the life of each product.