Wrap the clamp around the boot. The tabs will easily snap into one set of the square holes. Now unsnap it and put a small flat-bladed screwdriver through the next hole, then pry the screwdriver tip against the square pry tab, then lever the tabs into the holes. Now you can squeeze the crimp to complete the tightening operation - position the jaws of the crimping pliers on each side of the crimp, then gently squeeze the handles - if the crimp starts to lean to one side, reverse the jaws on the crimp and crimp a bit more. Continue to flip-flop the pliers if necessary, and compress the crimp until the clamp is reasonably tight. I highly recommend the special pliers made for this (picture); a decent cheap set can be found at any auto parts store for about ten bucks. They're worth it.
