1. Registration of related websites: First, you need to register an account in official website, Zhao Lixian's online mathematics course, and improve your personal information, then choose the course, fill in the delivery address, and finally pay the course fee.

2. Sign up on the official WeChat account: First, you need to pay attention to the official WeChat account of Zhao Lixian's online math class, then choose the online class in the official WeChat account, fill in the necessary information and pay the course fee.