Research your tutoring options. Large tutoring companies, such as Princeton Review and Kaplan, often have dozens of tutors on staff. You can also hire an independent tutor; many college students and high school teachers work part time as tutors.
Ask the tutor about her credentials. A good SAT tutor is not just intelligent and academically successful--she is also an excellent test taker. Most major tutoring companies won't hire tutors who scored below the 90th percentile on the SAT and it's acceptable to hold an independent tutor to the same standards.
Schedule a preliminary meeting to discuss the student's specific needs. Some students need intensive help in one particular section of the SAT, while others need to improve their general test taking skills.
Discuss price upfront. Ask about cancellation fees; many tutors charge a fee if you cancel a session less than 24 hours in advance.
Inquire about score guarantees. Most of the major tutoring companies offer to refund part--or sometimes all--of your money if the student does not improve his score by a certain amount.