I have also found that it needs to cost the mentee something. If we met for lunch for example, then I think the mentee should pick up the tab. I have picked up the tab for years, and all added up, I still got more than I paid for. Sometimes I got a college class in life, that was worth thousands.
The mentee should have an agenda and take notes while the mentor is speaking. Questions from the mentee help the mentor locate the mentee, and navigate him/her from point A to point B, quicker than trying to figure out what the mentee wants or needs. A good mentor is always listening to the Holy Spirit for direction and impartation, as to what God wants and needs him/her to deposit into the life of the mentee.