I missed an over/under on my first attempt, untied it and started over, getting it right with the second and third attempts shown in my photo.
I used around 3.5 feet of orange tether cord for the smaller cross, then did another with 4.5 feet of olive drab ungutted paracord, but you may use more or less depending on how loose or tight you work the cord, or if you want a longer loop out the top, or add a bead at the bottom with a knot to finish, etc... I've used fishing swivels for past projects, so I had a few stashed away to use with these, and probably a few more in a tackle box somewhere in the garage...
bobby pins to use as shown in the instructions, so I just temporarily lashed together a couple of my paracord lacing needles with 0.9mm cord to knot over, and just pulled them out when required. The paracord version looks to be just the right length to insert a small firesteel in the vertical section, for survival use on a zipper pull.
Another made without a swivel, attached to my Victorinox Silver Alox Lumberjack.
And one made with two colors, for use as a bookmark and shown with 'Strength for Service'.