+1 on using a gallon ziplock bag every few days for clothing. You can also use the bag to get most of the grime off your body before doing a wash or taking a swim to limit organic matter in the lakes and streams. One pair of undies is fine if washed often and if you practice good groin and backside hygiene.
If you wash up a little each day with some plain water on your head, face, neck and pits, then you’ll soon reach a low baseline level of grime on your body that’s very tolerable, even without soap. Every 3 days it’s nice to take a full bath, along with an alcohol wipe around the groin when finished.
For daily constitutional hygiene, I like to use an extended 90 degree squirt attachment for one of my unfiltered water bottles (700mL Smartwater bottle). After removing most of the poo with leaves or rocks, you can squirt the area well with the water, then follow up with just a piece or two of TP for “polishing”. Ending with an alcohol wipe of the area is also nice, along with a drop of soap and some water for the hands.