1. Determine the eligibility: First of all, you need to make sure that you are qualified to apply for mathematics at Cambridge University. Usually need to have a high school diploma or equivalent, and have excellent performance and ability in mathematics.

2. Preparation of application materials: Prepare the materials needed for the application, including personal statements, letters of recommendation and transcripts. A personal statement is a statement about why you chose mathematics as your major and your academic interests and goals. Letters of recommendation should come from your teachers or tutors, who can prove your talent and potential in mathematics.

3. Register and fill in the application form: log on to official website of Cambridge University and register and fill in the application form. In the application form, you need to provide personal information, education, academic performance and other detailed information.

4. Submit application materials: Submit the prepared application materials to Cambridge University as required. Make sure you submit your application on time so as not to miss the deadline.

5. Attend an interview: If your application is accepted by Cambridge University, you may be invited to attend an interview. Interviews are usually conducted by telephone or video to assess your math ability and adaptability.

6. Accept the acceptance letter: If you pass the interview and are admitted to Cambridge University, you will receive the acceptance letter. On the notice, you will find information such as admission requirements and admission date.

7. Confirmation of admission: After accepting the admission notice, you need to confirm the admission as required. This may include tuition payment, visa processing and other procedures.

8. School preparation: Before entering school, you can start preparing the articles and documents needed for school. In addition, you can also get familiar with the campus and get to know the preparations before entering the school by participating in the open day activities of Cambridge University.