To open a 1688 overseas merchant, you need to follow the following steps:

1. Register as a 1688 member. During the registration process, you need to provide information such as company name, contact person, and contact information.

2. Log in to your 1688 account and enter the "Overseas Seller Center" page. On this page, you can see a detailed introduction to overseas seller services and the application entrance.

3. Fill in the application form for settlement. The application form requires filling in basic company information, contact information, business scope, main products, and other information.

4. Submit the settlement application. After submitting the settlement application, you need to wait for 1688 to review it. After the review is passed, you can start selling goods on the 1688 platform.

5. Open an Alipay account. After becoming a 1688 overseas merchant, you need to open an Alipay account to trade on the platform. You can open it through the Alipay official website.

6. Publish products. Log in to your 1688 account, enter the "Publish Product" page, fill in product information, price, pictures, etc. according to the platform's requirements, and submit for review. After the review is passed, the product can be displayed and sold on the platform.

It should be noted that to become a 1688 overseas merchant, you need to provide real company information and abide by the platform's relevant regulations, otherwise your account may be blocked. At the same time, the 1688 platform will also conduct regular reviews of overseas sellers to ensure that their operations are legal and honest.