Step 1: Materials.
1. Duct Tape
... simple enough
2. keys... preferably on a key ring
also pretty easy
Step 2: Creating the Lanyard
2. Leave the end open and put the already folded end in .
3. finish the fold.
Step 3: The key portion.
(It can be anywhere in the necklace, but I find it more aesthetically pleasing to put it over the overlay).
Make sure to leave some room to slide the key ring into.