Book Reviewer
To become a professional book reviewer, you need credentials and an
established and recognized name established over a period of time. Most are published and recognized
authors or authorities in the field that they critique.
To become a reader reviewer, there are many online review sites that
are always looking for reviewers. Since it is mostly volunteer work
(online reviewers get the books free, some sites offer a few other incentives, but most do not pay salaries), the turnover tends
to be high, so there is usually some demand for them.