Gee my boys get dirty every day - but their clothes are small so the wifey packs enough spares so we can wash 3 or more days apart.
I'm a tight arse so a hand powered washing machine does the trick for our family with 2 small boys at the moment... (But we're usually only away for 3 wks at a time and I tend to go feral so less adult clothes to wash). We do use CP or laundromat mid trip too if we get too busy or need to wash something large. Promised the wifey I'd buy a washing machine outright instead of paying CP rates if hitting the road for more than two months but until then the deal is I do the manual labour... or cough up the gold ones.
Here's what I did/do:
1. Get a good size bucket (and a sealing lid if you want to drive n soak/wash).
2. Get a decent rubber plunger - best if you can get one with a handle the same size dia or thread as your broom's handle - or buy a broom stick to suit it... Replace the plunger handle with long stick.
3. Add washing (use biodegradable detergent when outback), stand up and work it baby. Get that plunger pumping - go hard for a minute or two and your done. Repeat with fresh water n detergent if needed for deep wash cycle then do the final rinse cycle with water only...
You will smash so much air n water through those clothes it's not funny.
5. A quick wring by hand and just hang it out quite wet on a sunny day. (Handy to have a good 10-15m bit of rope to tie up between van n tree for clothes line if free camping).
Any large items I just wrap around the bull bar or awning post, twist n pull to wring out all the water by hand. (Microfiber towels are great / dry real quick and take up buggerall space).
Ps. we take one of those large colored flexible plastic buckets and use it to bath the boys inside the van or out in the open air during warmer months, do the clothes washing, etc. Also found using an 80L storage tub out the back of the ute handy for doing large size loads once a week.
My washing machine also works with river/dam water when needed and allows the power supply to drink more beer at the end of the day.
Have fun on your trip
@NickM87
Ligedy