1. The Re-Draw / Erase button will clear the board and render a new sketch board. The value you enter determines the number of boxes for both the height and width, but doesn't change the overall sketch pad dimensions.
2. Move your mouse over the boxes you want to color.
3. Use the color picker to change the color you want boxes
4. The randomize checkbox overrides the color picker and generates a random color for each box you mouse over.
5. The build opacity option builds the color density of the box with each successive pass. Be careful, the boxes will retain the opacity setting even if you change colors and pass back over it, which allows shading!
6. Have fun!