We use plastic wire ties, you know those zip ties that you stick one end through the little one-way block on the other end. Here in NE the part of the tag that must be attached to the deer is a strip about 1 1/2" wide and 8" long, with a hole in one end. After notching or marking it we stick the tag through the hole, wrap the tag around an antler or leg and then the zip tie around it. I'v seen guys use string and even baling wire (this is farm country) to attach the tag. Just make sure that everyting on the tag is filled out correctly before you check it in.