How to Build a Broker Network?

Looking to hear from experiences building broker networks. How did you build a broker network to fuel your deal flow? Where did you find these brokers (assuming you defined your search industry and other parameters). How did you get these brokers to take you seriously as a buyer (let's assume you are doing a self funded search and you cannot point to the established investors backing you). If you have any resources on this, I would love to see them.

Thank you for your help!