Step 1: Open China UnionPay Express app and log in.

Step 2: Bind the credit card (or click authorize binding in the credit card interface).

Step 3: Open the QR code displayed on the credit card interface for payment.

Step 4: Enter a series of numbers on the back of the credit card and the validity period of the credit card, and click "Next".

Step 5: Enter the verification code on the short message and open the China UnionPay Express credit card to collect money.

It should be noted that it is not enough to bind a credit card. It is impossible to use the first credit card if it is not opened.