I think you're referring to the loop of the included lanyard?
Put the loop through one hole (you got that far)
option 1:
- spread open the loop
- pull the lanyard through the loop
- pull tight, lanyard fixed, but tailstanding is compromised
option 2:
- pull the loop out through the other hole
- spread open the loop
- pull the lanyard through the loop
- pull tight, lanyard fixed
Pulling the loop out through the second hole can be a bit tricky, I find it easiest to stick a piece of thin but stiff wire (like fishing line) through the second hole, stick it through the loop and back through the hole, now pull both ends of the wire to pull the loop through the hole.
Good luck!