For simplicity we refer to a mentor in the traditional or old time way. See more below. Tutors or mentors usually work with individuals to develop skills, talents and interests. Usually they help with a specific skill on a one to one basis either in person, on the telephone or on-line. Tutors are private teachers, normally contracted and paid to help students work on academic subjects, augment classroom teaching, help in preparation for examinations.
Tutors usually can tutor several individuals at once.
For some this is a full time job. Colleges, universities, classified ads can direct you to a good tutor. There are some volunteer tutors but most often you have to pay for their services by the hour. Mentors are similar to private teachers. They are wise and faithful guides or counselors, often retired or semi-retired benevolent and successful executives or experts.