I throw my feather pillows in the washer on gentle and wash them through a complete cycle, then I put them in the dryer with a couple of pair of old canvas tennis shoes. I have done this for over 30 years and do it about once every year or so. You do have to fluff the feathers as they dry. You can also hang them on the close-line, if you have one. Be sure that there are no little openings in the seams when you wash them.