To Measure you neck, take a piece of scrap paracord (or other sting ect.) and wrap it around your neck. Figure out how you want the necklace to fit and adjust the rope acordingly. I went for more of a choker style neclace but its up to you. Mark the length and measure the cord. Now to find out the amount of paracord you'll be using use this formula- 1in. of necklace = 41/2 in. of each color of paracord. For example, I'm making a 15in. necklace, then I'll need 67.5 in of each color to make the necklace. I would also recommend adding 1/2 a foot to a foot to each measurement just so you have some wiggle room. Cut and fuse the rope.