In my opinion, the Best way I found to do this is Not to ask for referrals, but display what it is you do and draw them to you by your expertise.  Videos I've found work best to display what you have to offer.  (Now displaying your expertise, assumes that you know your Brand & Who You Are or your Passion) Infuse whatever you are marketing with YOU and your Passion.  Using your Brand & your Passion, give Examples & ideas showing your Knowledge of the Niche market you are in &  your "Unique" approach to that Niche market. (the Uniqueness of You & your Brand will stand out) And when prospects see what you are doing, they will Find YOU.  No Referral needed, Make sense?  Hopefully you see this