I followed exactly the instructions on the Western Mountaineering website for product care, including using the Revivex down soap and DWR spray that they recommend.

My DIL has an extra large capacity front-loading washer and dryer, both with extra-delicate cycles, so I used those. With any machine, be sure to run a cycle or two with only water to get all the detergent out before you start. I cleaned the slot where the detergent is put in and then ran two full cycles to be sure (I could still see some suds at the end of the first cycle).

It took about 9 hours including the water-only cycles to remove detergent at the start, so if you go to the laundromat, take a big book, like War and Peace, plus tons of quarters. Be sure you find a machine with a delicate cycle, check the inside for snags and do extra rinses.

The WM website also describes how to hand wash in the bathtub, which is more work but at least saves hours of boredom at the laundromat!

You can also send it to an outfit that specializes in washing down sleeping bags, such as Rainy Pass in Seattle.

My sleeping bag ended up loftier than it was when I bought it!