Press number keys 1-8 to change the color- the top row will tell you the order. 9 clears the drawing space. Left and right arrow keys change backgrounds.
Thanks to @dwu1234 for helping me with the actual drawing All else by me. UPDATE LOG: Version 1.1: Initial release. Includes changing colors and actual drawing. Version 1.2: Added pen thickness and clear button. Sorry about the background to the pen thickness.....