Not my instructions; they are on the Western Mountaineering website. If those instructions are good enough for the Cadillac of sleeping bags, they're good enough for any down sleeping bag!

Mine also had quite a bit more loft after washing than when I bought it.

I'm not into jumping into cold water, but I do sponge off with a damp rag and lukewarm water (leftover from what I heat for dinner) in the tent at bedtime. I normally wear my base layers to bed--I never wear item for hiking except in colder weather than we get in the Pacific NW, so they never get sweaty. My hiking shirt and pants stay off; if they're damp they go inside a plastic bag and then in the bottom of my sleeping bag (they don't dry but at least they aren't cold when I put them on in the morning!). I also wear a cap to bed, which keeps the sleeping bag hood from picking up hair oils.