1. Purchase it directly at the hotel buffet restaurant. Choose the annual card according to the desired type and duration, and pay the corresponding fee.

2. Purchase on the e-commerce platform. Many buffet restaurants in the major e-commerce platforms have opened official flagship stores, you can buy the annual card on the platform, and enjoy the platform's preferential and cashback services. After purchase, you can get the physical annual card at the front desk of the restaurant.

3. Purchase through the official website. Some self-service restaurants also provide the service of purchasing annual cards on the official website, which generally requires you to register an account on the website, choose the type of annual card and the length of time you need, and pay the corresponding fees. After successful purchase, you can get the physical annual card at the front desk of the restaurant.

Different buffet restaurants may have different purchasing methods and policies, so it's best to understand the specific card purchasing methods and requirements of your target buffet restaurant before purchasing.