Mostly water from a spray bottle, wiped down with damp chamois, followed by dry polishing cloth (microfiber).
Every now & again I use ViewPlex, skip the chamois, go straight to the microfiber .
What do people use on their propeller??
I try get as much dried bug guts off with dilute detergent/water.
I follow this with a good quality automotive polish (usually 2-3 applications).
Finally apply a layer of Carnauba wax, to leading edges and rear surface - this I let dry and do not polish off.
The idea is that the dried wax will "shed" bugs more readily than the polished surface. I think it works.
I have also used this technique, on all leading edges, when on an away (multi day) trip - seems to save a lot of cleaning when I get home.