There is a small Phillips head screw in the tip of the tool. Tightening that screw forces the cutters open more thus making the hole in the link larger. Be careful with that screw, it doesn't take much to over cut a link.
by 2 turns he means, 2 complete rotations of the cutter. You want to take a little off at a time and check between attempts. You want the link to pop on firmly. It should have little friction once installed but not have any slop. If you are getting slop once popped on the ball, you cut it too much.
You will mess up a couple at first, just part of learning. The kit came with 1 extra. Go slow and check twice.
Once you get the technique figured out, it's a piece of cake.