Step 1: Materials
I lost mine because it wasn't attached so I bought mine at Walmart. You can use your original if you have it or get a new one at AutoZone, or any auto parts store.
Rope, a small chain, or some sort of cable can be substituted)
For melting the paracord ends.
I used a 1/4" bit.
Not too much, just a little while.
Something needing a fuel cap (re)attached to it
My 1985 Chevy Caprice Estate was the vehicle in need.
Step 2: Making the Hole
Make sure to hold the cap with something such as a vise or clamp so that it doesn't try to run away from you while drilling and you accidentally put a hole somewhere other than where it is intended.
Step 3: Attach Paracord Between the Cap & Vehicle
Step 4: All Done!
Depending on the type of fuel cap I think that you could adapt this to lawn mowers, generators or things such as leaf blowers and chainsaws. Also you can use a small chain or another type of cord. If you have suggestions or comments please let me know.