When I visited colleges, most of the tour guides I followed were walking backwards talking to our group. I suppose as long as one is guided to an unknown place by another, this counts as following no matter what because in either case they are proceeding to that point in front of you.
The question is if you want to follow the backwards walker. On one hand, they may be able to lead backwards because they have ninja-like reflexes, or some kind of second sight. In this case, you definitely want them on your side, and you should follow them as a form of appeasement. On the other hand, they could be very stupid for believing that walking backwards is advantageous over walking forwards. Perhaps you should question if following this urchin is really what you want to do.
The more pressing question is can you follow someone walking backwards? If you don't know where to go and you can't see the person you're supposed to follow, how do you know where to go? How can you check to see if you're still behind the one wearing the hat that says "follow me". You can look over a shoulder, but then are you truly backwards? You peek anyway, only to discover the individual with the hat is gone, but you are walking behind another. Maybe its the same person but they took off the hat, or maybe its a different person entirely and you're lost. There's really no way of knowing. Maybe it's time to man up and walk forward next time, or perhaps not. You ended up exactly where you needed to go. Was this the plan all along? For just a second, the man with the "follow me" hat reappears and gives you a grin that's hard to place, only to walk backwards into the crowd and disappear.