1. Download the official App of Sam relatives and friends card: First, users need to download and install the official App of Sam relatives and friends card on their mobile phones. This app can be found in app stores, such as App Store or Google Play.

2. Register an account or log in: After opening the official App of Sam Family and Friends Card, users can choose to register a new account or log in to an existing account directly.

3. Find the QR code option: In the main interface or menu of the App, the user needs to find a specific option, usually the option marked with the name "QR code" or "My card".

4. Click Generate QR code: In the QR code option, users can choose to generate their own QR code. After clicking the relevant button, the system will automatically generate a QR code related to the user account.

5. Show the QR code: After generating the QR code, the user can light up the screen of the mobile phone and let the cashier or waiter scan the QR code. In this way, users can use the benefits or services provided by Sam's relatives and friends card.

The reason why the QR code is designed and presented in this way is to facilitate users to use the Sam relatives and friends card and provide faster and more convenient payment and preferential services. The QR code can be displayed on the mobile phone at any time, which eliminates the trouble of carrying a physical card and provides more functional options, such as checking account balance and consumption records. In addition, the use of QR code can also improve the security of payment and prevent the risk of card information being stolen or lost.

Extended content: With the popularity of mobile payment and electronic card vouchers, more and more membership cards and discount cards are in the form of QR codes. As a fast, safe and easily identifiable technical means, QR code can be widely used not only in retail, catering, entertainment and other industries, but also in public transportation, electronic ticketing and other fields. By scanning the QR code, users can conveniently enjoy membership rights, preferential prices and personalized services, and businesses can also better manage membership information, promote activities and conduct data analysis. Therefore, the use of QR code has become an indispensable part of modern life.