1. Pick up the paintbrush on the bottom right corner.
2. Select the paintbrush from your inventory and rub to clean the white smudge above where you picked up the paintbrush.
3. Press the number "16" where you cleaned the white smudge and the squares should turn into colors.
4. Now change the colors of the squares so it looks like the following (left to right): Top row: Orange, light blue, blue Bottom row: Green, pink, yellow