I made some of these a couple months back and found this one on the floor under the bed this morning. I make so many variations of things but only post a fraction of what I make on this blog. It's a simple one if you can make the monkey fist.
I used about 5 feet of paracord, first making a monkey fist around a small marble. Then making sure the two strands coming from the fist were equal in length, I looped them around the key ring about 2.5 inches from the fist and made the snake knot back towards the fist around the two strands coming from the monkey fist, and trimmed/melted the ends at the base of the fist.