a mentor can be anyone really just someone you trust to help you learn greater magic's. If a mentor trusts you its because they think you may be capable of doing what others can't. Yes it takes a while to find one if you have a rep for fluff but if you go to my other post you can find ways to avoid it fluff for noobs. I personally find my students by finding there compassion and i know when there being a kiss butt to me thats how i rule them to the bad list of people i know. If you are a mentor in training kiss butts only want you to defend them and take advantage of nicer people then them selves. Mentors could be family friends or me if you want a mentor on something you could go to me but i will never lie and always be straight forward with you.
I'd also like to state that having multiple mentors can be tiring but can be beneficial. You can learn more than one point of view and indeed decide what your point of view is from there. Also, many mentors don't like their student to have more than one mentor, so if you plan on having more than one make sure it is alright with them first.