Let's see, this is something like what I usually say:
"Okay, you guys know how to play? Okay, how do you play?
(No one seems to remember) Yeah, I thought so. Okay, the object of the game is to get the front of your car under the green lights and the red lights.
(Sometimes I add
You'll see the lights shining down on the floor, and you want to get the sensor on the front of your car under the green lights and avoid the red lights.
"Please keep your hands on the wheel at all times; don't take your hands off the wheel for any reason. If you take your hands off the wheel, the car will shake. If the car shakes, take your foot off the gas, make sure your hands are on the wheel, and then put your foot back on the gas. The gas is under your right foot; it's a little red or a white button. Don't get out of the car, don't run across the floor, and have fun."
The #1 thing I have to tell people is "Hands on the wheel, please." The #2 is "Don't run!" I also have to tell people to turn the wheel, and sometimes I have to venture onto the floor to help someone if they seem stuck, or to move cars in the middle of the floor (always a fun task).
