How can I set up Apple Pay on Apple Watch?
Open the Apple Watch app on your iPhone.
Tap My Watch, then tap Wallet & Apple Pay.
If you have cards on your other Apple devices, or cards that you recently removed, tap Add next to a card you want to add, then enter the card’s CVV.
For any other card, tap Add Card, then follow the onscreen instructions.
Your card issuer may require additional steps to verify your identity.