Make sure Apple Pay is set up on your iPhone or Apple Watch
Check that the store accepts contactless payments
Open Wallet if needed, or be ready with your device
Double-click the side button on iPhone with Face ID, or use Touch ID if prompted
Authenticate with Face ID, Touch ID, or passcode
Hold the top of your iPhone near the contactless reader
For Apple Watch, double-click the side button
Hold the Apple Watch near the contactless reader
Wait for the checkmark or confirmation on the screen
Keep the device near the reader until the payment is complete