The polyester cord has two knots. Simply pull them away from each other until there's about an inch between the knots and you can pull the necklace over your head. To tighten, tighten one knot at a time until you have your desired length. The chain has a copper clasp that you can feed through any link in the necklace you'd like. You can pinch the copper clasp together so it doesn't slip out of the link.