The mentor program is the best way to go. Then you'll be able to get help writing your reviews as well as someone to go to when you have questions about how things work. Once you graduate from the class, you'll become an advanced reviewer automatically.
You cannot get an assignment until you are an advanced reviewer. You can review as many times as you want to, but the reviews do not count towards becoming Advanced. I agree with Kira, try the mentor program, your mentor can help you with the site, reviews and graduate you to an advanced status when you are finished with the classes. Read their specialties and get one that is compatible with you and your partner!! Good luck--look forward to seeing you around the site!