Hold down the mouse and drag to paint! Click the icons to change the pen colour, erase or clear. Change the value of the 'width' variable to change the pen width.
I have spotted a problem and don't know how to fix it. The magic wand sprite is just meant to turn the pen colour to white so it can be used as an eraser. However when magic wand is selected you cannot drag the pen to erase, you can only make white dots. Also you cannot then select any other sprite to clear the screen or change pen colour back to blue or green.
