|Find the turtle.|
As you probably know, Common Snapping Turtles are not a species you want to mess with. They are very aggressive out of water, and typically much more relaxed in water; however, even in water they can and will hurt you if it perceives you as a threat. Honestly, just don't touch these guys. There's really no safe place you can touch them, as their neck is extremely flexible and can reach just about anywhere on their body. If you see one, give it space.