WeChat Pay is a mobile payment service that is integrated into the WeChat app, which is a popular messaging and social media app in China. Here are the steps to set up and use WeChat Pay:

Download the WeChat app on your phone and create an account, if you don't already have one.

In the WeChat app, go to the "Me" section and select "Wallet."

Select "Bank Cards" and then "Add a Card" to link a Chinese bank account or a credit card to your WeChat account.

Once your bank account or credit card is linked, you can use WeChat Pay to make purchases or transfer money to other WeChat users.

To make a purchase using WeChat Pay, simply open the WeChat app, navigate to the "Wallet" section and select "Pay."

To transfer money to other WeChat users you simply need to navigate to the "Pay" feature within a chat with the person you want to transfer money to.

It's important to note that for most Chinese, linking a Chinese bank card is mandatory for using WeChat Pay, and also you may need to complete a verification process before you are able to transfer money or make purchases with WeChat Pay.

I hope this helps! Let me know if you have any other questions.