It is required to become the course reader of your chosen class, your grade in that class had to be B+. However, it is much easier to get in if you have an A. Then, you ask for a form from the reader supervisor, and then ask for an interview with the professor to get their approval. Once it's done, you will sign a contract with the supervisor where you will be asked your social security number. For international students, they require for your I-20, student Visa, and passport's front page