[oldE]

Easiest thing I've fornd is olive oil.
First use a half oz. of olive oil to remove all the dirt. It will also dissolve grease, etc.
Then use liquid hand soap without water to breal up the oil's cohesion.
Then warm water takes it all away.
A friend of mine who is a house painter clued me in on the stuff.
It works.
Oh, and if the weather is making your fingers crack, just rub in plain old vasiline.
That works too.

Best
Les