Press the arrow keys and space bar as they appear on the top board. Your score is displayed on the bottom board. To increase your score hit the buttons in time with the images. Every time you hit a button out of turn, your score decreases. Once you miss it 15 times the game ends. However, if you don't hit any buttons your score doesn't change. Once you hit 15 incorrect, hit an arrow key again to quit.
The idea is loosely based off of Dance, Dance, Revolution.