Where are the best examples of advisory board contracts?

I ended up in a conversation with a food startup in need of some help/guidance but unable to pay for a new position. It falls within an area of interest to me, but I want to create a relationship that goes beyond and is more beneficial than ad hoc volunteering my time. I will be the only marketing professional in the mix as well as the only one with industry experience.

Where resources can I use to make sure this relationship gets off on the right foot?