I started painting planks in my yard and quickly found than

I was ruining the concrete surface of the yard.

The yard is concrete with coloured pigment in it with a smooth

finish but now it has lots of spots of water based semi gloss

paint.

What is the best way to clean it off.The coloured pigment is not sealed

with varnish or anything.

Ever hear of a thing called a drop cloth?

Let it dry and try a pressure washer or scraper.