I had some really crappy old worn out baby blanket things, just cut them into squares and overlocked them. I have a little dish of water where I change nappies, and just dip them in that before wiping. If it's a real pooey mess, I use a proper baby wipe first, then a cotton wool ball dipped in water, and then lastly the cloth wipe. Just makes things a little easier for me.
I also cut a terry flat in half and overlocked the edges to make two smaller cloths which I use to wipe DD's bum dry!