Another idea is they make a cement mixer. It is a small plastic bucket about the size of a 5 gallon bucket. It has paddles inside for agitation. In essence you roll it around the yard to to mix. Might also work for cloths.
Used to be a small-batch cement mixer that was a poly drum, maybe eight or ten gallon size, with molded in fins to stir the mix. The intention was that you add the cement and water, put on the top and roll it around the yard. You could mix, perhaps, one or two cubic feet of cement at a go. I used to see them sometimes at the larger hardware stores. I always suspected that people underestimate just how hard rolling a drum full of liquids can be.
Once saw a brick man who had a mixer that was set up as a small trailer. Flip a lever and the wheels were geared to the drum. His helper would shovel in an appropriate mix of sand and portland, add water and tow the unit around the block to mix it up. Worked pretty well from what I could tell. Of course gas was cheap back then also.