The easiest way to use money from international bank accounts in China is to open an Alipay or WeChat account and bind your bank card. Detailed instructions can be found here:
https://mp.weixin.qq.com/s/r6VX-V7GnDrtgT2afO1tsQ
It is possible to use cash but in many places it may be hard to get a change because the common way of payment is Alipay or WeChatPay. For this reason, we recommend opening an Alipay or WeChat account before traveling to China.
A QR code generated in Alipay application can be also used as a pass for metro and bus.
