I almost exclusively boondock.
I never carry more than 3 gallons (and only carry 1 if I know I’ll be near convenient water) — water is heavy and takes lots of space. I carry a water filter to help replenish supplies. In desert areas, conservation is necessary.
A paper town moistened with rubbing alcohol is a good substitute for showering as it kills bacteria that cause stench. Proper water sources like streams and lakes make life easier.