the molded information (brand, size, etc.) should be away from the engine--the nut should tighten up agains it. I'm assuming you're talking about a traditional front mounted engine, and not a rear-engine "pusher." The prop will turn counter-clockwise when looking at it from the front. While turning that direction, it should blow air back, toward the aircraft. The leading edge will be the fat edge--just like a wing's airfoil--and will taper toward the trailing edge.