You don't wash.
Especially wool and silk do not need washing regularly. Still some stains? Try natural soap (ox gallow). If your pretty sweater still is smelly, you can use mild detergent in a handwash. Do you take a shower every day? Take some clothing with you to steam and then take them outside. There might be some professional eco steam shops around in your area. However, if the stain or smell is too much you can try chemical steam. Delicate textile will also stay fine in a special program of your machine wash. As a last resort, upcycle your wardrobe! See examples in my webshop and contact me for workshops.