Every other day, but I only wash my hair every 4th day. It goes up in a shower cap for the body shower that happens in between hair washings. My hair is thick and past my bra strap at this point, so washing is a hassle.
Between hair washings I brush baby powder through my hair.
Also, when I shower, I only use shower gel on the parts that need washing, if you catch my drift. Unless I've been very sweaty or put sunblock on, I don't wash, for example, my arms and legs, or the skin on my torso. My skin dries out easily and putting soap on those areas isn't necessary (I certainly don't smell!) and can definitely dry me out. I apply lotion after every shower. I don't think I could even get away with showering everyday on a regular basis. I'd turn into a big skin flake, lol.