Ever. I toss them in the washing machine. If they're blue, I put them in the hot water with the towels, because I'm a poor college student and the washing machines cost money. The colors go in cold. The whites are washed cold with whites. Throw them in the dryer on delicate setting, pull them out and hang them up right when they start to go dry. If necessary, hang them up in the tiny suite bathroom (actually a plus: the room fills with steam incredibly well) for about ten minutes with the shower on hot. They don't look perfect, but I had one white shirt pressed and did one my way, and a friend couldn't tell the difference once I was wearing them. It probably helped that they were twill, but I'd still say my system works very well.