Basically, following back from the end, taking every turn you can, tells you the right start and the right way forward. If you go from the start you end up at and from there go back the way you came you can get to the finish.
Umm, for me the instructions make it even more confusing now. Kiethy I am not sure how is it meant, what is it about the follow back system, why do I have to follow back? Is there some other clue you mean other than what azz said?
You need to get through the course without hitting the motion sensors (which you can see poking out of the walls slightly) at least that's what I think.