That's OK...I guess. I'd much prefer a solution that is cord only, using a break-away knot. A search of the internet didn't yield exactly what I was searching for, so I tried my own design.
Here's how I did it.
Step 1: Start with about 60 inches of cord.
Step 2: Make a bight 24 inches from one end.
Also, the diameter, and the stiffness, of the cord you choose to use will affect cord length. Be prepared to be flexible and innovative!
Step 3: Tie a decorative knot.
I chose to tie a Diamond Knot (Boatswain's Whistle Knot). Stormdrane recommends this page to help learn the Diamond Knot.
Any decorative knot will work. The Celtic Button Knot is another favorite of mine. Tie it along a single strand of cord and feed the bight back through, following the original strand back out, to form a loop.
However, the Diamond Knot is much simpler, and makes a smaller, more compact knot than the doubled Celtic Button Knot.
These dimensions were designed to fit a split ring with a diameter of 1-3/8". If you'll be attaching the lanyard loop to a ring of a different size, adjust the loop length as needed.