Warning:

If you are riding a bicycle, I highly recommend against sticking your feet in your spokes. Although the world seems very interesting when viewed upside down, macadam and concrete surfaces typically retain their non-porous, non-elastic properties regardless of the rider's vertical orientation.

If your friends stick their feet in your spokes, there isn't much I can tell you that will be of assistance. Perhaps, "Get some new friends"?

More advice? Watch out for Belgian cross fans, square edged walls, rails, and ponds. And you might want to just think about wearing a helmet. And I don't have a clue about how you avoid this stuff.

You may want to think about not jumping your mountain bike over the Peloton in the Tour de France... the Gendarmes get really funny about things like that.

And last thing, if you happen to see a motorcycle-borne camera during your pathetic citizens' race, do not mug at the camera in lieu of keeping your eyes on the road. Unexpected Expected things may happen, and you could end up with your 124 closest friends all wanting to have a discussion with you at the same time.