Press E for Instructions, Press space to initiate, and press 1 to clear. There is no save feature! I recommend using screenshots to retain save data. Import your own costume in sprite 2, go to sprite 1, and select a color on both the "if" block and the "pen color" block. Press space, and boom, it will show you anywhere and everywhere that color is.
Thanks to Ryder for the help with the coloring system! For info, I have a personal edition for myself that I am using to improve upon this. So this might be updated soon, maybe check back soon?