I got this picture from www.engrish.com and it sounded strange... In mandarin (if i'm not wrong, because my Mother Tongue is very bad), it means "Please beware of falling over the fence", how would the action of me turning over (which I assume means to face another direction) cause me to fall off the fence if I'm not even touching?
There is dark magic going around if you 'turn over'!!!

*Adeline*