Choose a shape for the robot to draw. Click him or press space to clear the screen and reset him ready to draw something else. Or just pick new things (when he's finished a drawing) to draw over the top without clearing.
I am attending the EdX class on learning Scratch (Programming in Scratch - HarveyMuddX - CS002x) This is the exercises from the 2nd Lecture: Drawing. It's not quite finished but Zebry was nagging me to share it already!