Listen. - A little direction goes a long way.
When I mentor people, I try to let them speak 90% of the time. I ask questions and I listen, for two reasons. The first: learning to listen is one of the most important things a person can learn. When my mentees see how much I listen to them without interrupting, they listen to me the same way. Get to know their whole life. Once you start learning about one area of a person's life, you have more to reference when you learn about other areas of their life. It all adds up and you can tailor better solutions for them as you get to know more about how they tick.
How to build respect
Get to know them. Get to know what they respect, and highlight those things in your life. But have a strong character of your own, a character that is good, wise, and caring. Kids that are still developing their characters respect those who are further along in the development of their own - though they will find in their journey with you that everybody's character will develop throughout their life.
Explore Together
That is my first rule of mentoring kids. If I have knowledge, I can impart it, but the best place to be is where I know more than they do about how to get the answer, but I don't know the answer myself. There is nothing less motivating than an omniscient teacher. My mentees get the most excited when they figure something out that I don't know - or rather, something that didn't know until I pointed them in the right direction and we discovered something new together.
Enthusiasm and Humility
When I work with kids, I think, "These people are brighter than me, more open minded than me, and, (partly because I'm helping them!) they have a brighter future than me." That helps keep me humble. All of the kids that I work with are hungry for knowledge and hungry for understanding. In them, enthusiasm sparks easily. A mentor just has to be there to tend to that spark until it becomes a flame.
The mentor should regularly talk with the mentee's parents about the mentee; the mentee should talk with the parents about the mentor: they should all explore their relationships, they should all know what is going on with each other. Kids need to learn that relationships with everyone around them are important, especially their siblings and father and mother. When they learn to do this in an open, appropriate way, they are able to walk through life so much more easily than people who don't know how to relate to those around them.
Distinguish between long-term and short term goals:
Some things you can make come true now, other things you can only prepare them for.