Host and promote a competition. You can call it “The Great ____________ Race.” Set up a small number of teams, each with a small number of participants. One team wins upon accomplishing the appropriate task you set before them. The entry fee may be the cost (or reduced cost) of your service. The grand prize can be more of your product or service, or you may find a sponsor to provide the prize(s) in exchange for promotion through the event.
Variation: Donate your product or service to a charitable cause in the winner’s name.