Using gloves for some things and handi-wipes (Wet Ones) after other things helps cut down on running the sinks for hand washing.
We're heading out on a 3 night dry camping weekend with similar tanks and will do fine with us likely taking 1 Navy shower each during the weekend.
I bring an empty 6 gal water container on trips like this in case I need to refill, but haven't needed it (yet). I also have a Water Thief in case I can run a hose from a spigot without threads.
There are all sorts of tips available for efficient water us. Like running the shower head into a tub while waiting for hot water, then using that tub to wash or rinse dishes later.
