Take subject tests to determine what you are eligible to teach, then conduct a tutoring session with a mentor as the student. Use all available tools (whiteboard, etc.) and you should have no trouble.

First, you would take competency tests to see which subjects you would tutor. Afterward, you communicated with a tutor mentor to schedule a 1 on 1 session where you would have a mock online session. If you passed this stage, you were hired.