You can make adjustable slide knot necklaces with leather cord. The two sliding knots that are tied at the ends of leather cord necklace are called slip knots. The way the slip knots are tied allows them to slide back and forth along the leather cord. When the knots are slid apart on the cord, the necklace shortens; when they are moved back together, the necklace lengthens. Slip knots secure the necklace together while allowing its length to be adjusted for removal.
Thread the beads onto the cord, placing the focal point bead or pendant in the middle of the string of beads. Slide the beads over to the middle of the cord. Tie a simple overhand knot at both sides of the beads to keep them in the centre of the cord.
Hold the cord ends together so that the cord forms a necklace shape. Put one end under the other in your hands. Pull each end over to its opposite side so that it overlaps the main part of the necklace cord by four inches. Hold onto one end of the cord, place your thumb onto it one inch in from its end, and your index finger on the cord that it is overlapping. Pull the end of cord under the bottom of the main part of the necklace. Thread the end through the loop you just made and pull it shut to make a loose yet secure slide knot.
Tie the other end of the bottom cord in the same fashion, bringing it under the main part of the necklace cord. Thread it through the loop you just made with it and pull it shut to make the second slide knot. Tighten the knots so that they won't come undone, but not so tight that you can't move them. Slide them back and forth on the leather cord to determine how tight you want them to be and tighten the knots.