I introduced my husband to the "indian" shower method back when we were camping last year.
Put ~3 gallons of whatever-temp water you get from the pump in a bucket. Add one smallish pot of boiling water, heated on your camp stove. Using a plastic measuring cup (or your tin coffee cup, or whatever is handy) pour enough tepid water over your person to get wet enough to lather. Soap and shampoo (biosoap, please!) then rinse with tepid water. If you have long hair, condition and rinse again.
All in a 3'x3' tarp enclosure hung up in the woods back behind your tent.. Oh yeah, and do this wearing flip-flops standing on a plastic milk crate or suchlike so you don't end up standing in the mud. Fun!