Add value to them before seeking the relationship.  When I worked in the media I was a gateway for people having access to our station air time.  Hands down the ones that knew something about me and our station, or that took the time to send a free offer to whatever they were trying to promote got in the door light years ahead of anyone else. 

I understood what they were doing was marketing, but I respected the fact that they took the time to add value to my life, before asking for the keys to the gateway.  Every time before the program ended I had told those people that I was rescheduling them for another guest appearance six months out. They got double their marketing efforts because they understood how to build a relationship. It's really never all about you.