Mentoring could be called "thought modelling." It's the saying about "teach a man to fish" -- that teacher is the mentor. Show a person the tools and how to use 'em, and you've mentored.
Did I mention you also have to have the right balance of knowledge and temperament, time and interest?
They also say "you can lead a horse to water, but you can't make 'im drink" and that's what you get for all your marvelous mentoring if the protoge is not with the program. So, the protege should really read the OTHER Crisp book for THAT role: www.tiny.cc/Protege.
Good little books (and inexpensive, too). Well worth the 90-minutes to read them both.