I don't. I wash every 2nd or 3rd day. I don't wet it on the days I don't wash, I don't see the point. the whole point of "second and third day hair" is that you DON't wash/soak/re-product it. otherwise it would just be a "no shampoo day", not "second day hair" .if my hair looks 'wonky" on a no wash day I put it up. Works for me. I know that giving my hair a one or 2 day rest between washing makes it look better overall & when I do wash I get 100% less frizz, probably because allowing my scalp's natural sebum to condition my hair without stripping & rinsing it away everyday . my hair looks a million times better since I started using sls free shampoos & silicone free conditioners & styling product. Another key point is i don't put much product in, just a touch for some definition. The more stuff you put on your hair, whe worse it will look on a no wash day. just my own personal experience.
"It's not having what you want, it's wanting what you've got"