-Choose your Mii at the main menu to make it do different things. If you choose its right arm, it will give you a thumbs up. If you choose its left arm, it will wave. If you choose its head, it will shake it. If you choose its torso, it will jump. If you choose its right leg, it will lift it up along with its hands. If you choose its left leg, it will act as if it is about to fall.
-After first reaching the finish line on Stampede, go to the Wii Play main menu. In the background, you will see other Miis that are on your Wii walk across the screen. They may do the things that the Mii you are using does when you click on various parts of the body. A few might fly across with a swimming-like motion. The only "click action" the background Miis do not do is the one where their eyes temporarily become round.