To open an AliExpress Alliance, you first need to follow these steps:

1. Register an AliExpress account: First, you need to register an AliExpress account. Visit the official website of AliExpress, click the "Free to Join" button, and then fill in the relevant information to register.

2. Create a store: After registration, you need to create your own store. Enter the AliExpress management backend, click the "Create a new store" button on the "My AliExpress" page, and then fill in the relevant information as required.

3. Complete the store information: After creating a store, you need to complete the basic information and information of the store. For example, the store name, store logo, store introduction, etc.

4. List products: After completing the store information, you can start listing products for sale. In the AliExpress management backend, select the "Product Management" menu, then click the "Add Product" button, fill in the product information as required and upload product pictures.

5. Join the AliExpress Alliance: After the store is created and products are listed, you can apply to join the AliExpress Alliance. In the AliExpress management backend, select the "AliExpress Alliance" menu, and then follow the page prompts to apply.

6. Review and activation: After applying to join the AliExpress Alliance, your application will be reviewed. Once the review is passed, your store will successfully join the AliExpress Alliance, and you can then enjoy the corresponding alliance rights and services. It should be noted that the specific process of each step may change due to the update of AliExpress. It is recommended to refer to the official documents of AliExpress or contact AliExpress customer service to obtain the latest operation instructions when performing operations.