A buffalo horn bead and black wooden beads are threaded onto a piece of waxed cotton cord with knots.
1. Thread a horn bead and a wooden bead onto a piece of cotton cord using a beading needle.
2. Tie knots onto the cord before threading any beads onto the cord. The knots function as stoppers for the beads.
3. Close after the beads by tying a knot onto the cord.
4. You may use a needle for pulling the knot as close to the bead as possible.
5. When the necklace has the desired number of beads, make an adjustable knot on either side of the cord.
See Jewellery School - An Adjustable Knot
Another variant.