After trying out several different types of Chinese knotting cord we have finally found one we love. This nylon cord has nice texture that helps to hold knots in place. To keep it from fraying you can melt the ends with a Thread Burner, or use Hypo-Tube Cement or super glue.
Hard to find kelly green CKC! A little expensive on the 10-yard card, but nice to be able to get a small quantity of many colors. 4 strand kumihimo gives you a 4mm braid--very nice cord to work with. :-)