how to use the codes? i cant seem to find aby option

It's possible only on the app

Enter the code when you sign up

How to use codes ≥
http://imgur.com/a/MNtBEur
Find mature section on the site >
http://imgur.com/a/GBeHac5
Ways to get 1nks without spending actual m0ney > http://imgur.com/a/7dbRddk
What happened? >
https://imgur.com/a/1lzvRGo