I got together some supplies. A cookie sheet, homemade water color paint/paste and his art smock and together we sat on the floor. I watched him, as at first he was hesitant to touch the paint. Then he banged the pan, until finally he put both his hands on to the pan and rubbed the paint around. Then he jumped face first into the paint, until he was finally eating the pan and paint off his hands. I love watching him as he discovers new things.
To make the paint I just mix flour and water until it was a good consitency and then added a defrosted raspberry puree cube so that it was ok for him to put it in his mouth.