Scattered across each level is an array of shapes in varying colors. As you move your mouse across the shapes, you'll eventually find one that will give you a "ping." This will be your starting point. From there, keep moving from shape to shape, finding the pattern of shapes that will give you more "pings." If you get a "whoops," you've made an error and need to start back at your first "ping" shape. As you find the "pings", a bar at the top will shrink, and eliminating it means you've cleared the level.
But this game isn't entirely trial and error, and Tonypa makes sure you're well aware of it. Every time you get a "whoop," you lose a life, and once you get 50 "whoops," it's game over ("wah-wah-wah-wah"). So how do you know where to go next? Well, just about every level has some sort of logical pattern that when followed correctly results in the correct path of "pings." I don't want to spoil the nature of some of the puzzles, since the fun of this game is in the discovery of the solution.
Cheers to Casey for suggesting this one! =)