To add a credit or debit card on your iPhone, open Wallet and tap + in the upper-right corner. (Note: If you do not see the + symbol in the upper-right corner, swipe down and it should appear.)
If you have a Liberty FCU credit or debit card on file with iTunes, you’ll be asked to add it. You can also choose to add a different card using your iPhone’s camera or by entering your card information manually.
To add a credit or debit card on iPad, go to Settings > Wallet & Apple Pay, tap “Add Credit or Debit Card” and then follow the same steps for iPhone above.
Keep in mind, the first card you store in wallet is your default payment card, but you can always change that in Settings.