C.H.
Considering I've fallen on hard times myself, I am very glad that I cloth diaper. I sewed my own from flannel sheets.
Simplest thing would be to use old receiving blankets for that age. Look up diaper folding instructions, I would use the origami fold. Very easy. For the heavy wetter, use a washcloth in the diaper as a diaper doubler.
Next you would need a diaper cover. Use Fleece pants. Fleece pants are also very easy to sew. I've made some out of some fleece hoodies and jackets I picked up at the good will store.
I am very glad I have a sewing machine because it helps a lot. But I thought not everyone has one, so the suggestions I put out are for those who don't need to sew.
Rinse in cold water, wash is hot water using a very small amount of detergent. Excess detergent causes buildup on cloth diapers. I literally use 1 tsp of soap. Extra rinsing is preferrably to more soap. If diapers smell, they may need to be stripped. Wash fleece separately so you can add fabric softener to add to the water resistance. Skip the fabric softener for the cloth diapers.
I also use washclothes as wipes. I just use warm water.