Space to change pen color, and the pen colors are listed below. The pen color is next to to "Next page" button and click "Next page" to clear your artwork.
dark green, bright green, bright red, dark red, black, pink, yellow, sky blue, dark blue, grey, purple, brown, orange, small eraser, and eraser You can add the word "fill" to every pen color (Not the eraser) to make the pen bigger. Press D to be able to see your artwork better.