Rotate Vehicle:
On the "Adjust Your Machine" screen, press the C buttons to view your vehicle from different angles.
Change Vehicle Color:
On the "Adjust Your Machine" screen, press the R button repeatedly to scroll through the various color jobs.
Shrink Vehicles
On the "Vehicle Select" screen, while holding the L and R buttons, press left C and bottom C simultaneously. All vehicles will be small until you complete the current circuit.
Get Everything:
On the Main screen (where you pick your mode), press these buttons in the order they appear: L, Z, R, C-Up, C-Down, C-Left, C-Right, then Start. If you did it correctly, the screen will blur, then reappear as normal. You will also hear a sound.