Click any square and move it around with your mouse, then press space when you want to place it down (it will shrink.) The yellow is to make the cat turn clockwise, pink is counterclockwise. The white square is to place over a single other square that you want to "erase." Press "K" to move the cat back to its original position, and "L" to erase all squares. Click the cat to start! Have fun!
Also you can place the white blocks over the black lines to prevent the cat from teleporting back when it touches the black line.