Advertisements. If you can advertise in any way, to any company, use it. My highschool sells full page ads in the yearbook for $700 ea, and we usually get up to about $250,000 from Sept. 28th, to October 18th. Give each person that sells an ad a 10% cut, and you have some incentive.
How you wanna refine the idea, and advertise, is up to you