Press space key to scribble, and press 0 to switch to a black canvas. Press 1 to switch back to a white canvas. Press 2 to turn on music. Press 3 to mute the music. (cringe music) Press 9 to draw and press 8 to stop drawing. Press 7 to make the lines thicker. Press 6 to make the lines even thicker. Press 5 to make the lines thin again.
Still figuring the pen thing out. Experiment!