Bank of China foreign exchange reservations can be completed through mobile WeChat. The specific steps are as follows:

1. Open WeChat on mobile phone, search for "Bank of China WeChat" and click to follow.

2. After paying attention, enter the "Bank of China Micro Banking" official account, click on Micro Finance, select more functions in the pop-up options, and click to enter.

3. After entering, click Bind and Unbind under "My Debit Card" or "My Credit Card" to bind your existing debit card or credit card.

4. After the binding is completed, return to the homepage of the official account, click on Micro Life, select foreign currency reservation in the pop-up options, and click to enter.

5. Enter the foreign currency reservation interface, select the type of foreign currency reservation you need, such as US dollars, then select the reservation outlet, and click Next.

6. In the pop-up interface, follow the prompts to enter the cash withdrawal information, and click Finish.

7. A confirmation information interface will pop up. After verifying that all information is accurate, click OK to confirm that the appointment is successful.