There are several different ways to do it. Amy, one of the SA moderators, throws hers into a lingerie bag in the washing machine, along with some towels. I'm too chicken - I just wash mine by hand in the kitchen sink with Dawn detergent. Another idea came from Anne Matasci's upline, who washes hers in her dishwasher's silverware basket with the little lid down to keep 'em from getting out.
I hope you are having a wonderful Sunday! I'm off to my upline's all-day stampin' Christmas Blitz. Trying to get my cards finished today!!!