Press arrow keys to move. Don't move too quickly or your game is ruined. You can freely step on green squares, but you can't on red. In level 2, brown squares appear making it as a threat. Touching on brown squares will result you in going into a level back (For ex. : Your in level 3, but you touch the brown squares so after that, your in level 2). You can also freely step on the gray squares. Gray squares don't do harm to you. Gray squares are just decorations but that doesn't mean they are not functional. The gray squares territory means that there will be brown squares everywhere around the territory which in your mission is to get past and don't touch the brown squares. That's all bye. Also remember the game is in demo, so it might not work as it's supposed to be.
I credit my teacher for doing a lesson that we made something like this. I just remade it, what we were doing at the lesson. Also. See the video here : https://www.youtube.com/watch?v=qp-pqvpf4cw&feature=youtu.be