IBY should have a referral program section at least in My Account if not its own standalone section. Minimalist would be showing the client's unique link for relevant referral program with a simple click to copy like how internet companies do for stupid-long passwords, etc. I'd also make a QR codes so that people could just show friends a QR code just like you do for Venmo, etc.

I argue for its own section, which would list the referred clients and some metric of those referrals (not necessarily how much they spend) like if they've booked a session or not so that referring clients can track how they're doing and what rewards they've earned. I'd include a status indicator in the referrals section with the top status being something like "Brand Ambassador" along with some description about what you get from whatever promotion or status level you've achieved. This is serious: Hamilton Helmer talks about network effects in his "Seven Powers" as something that can help a brand create long-term differentiation and ability to outperform competition in the long run (others are things like "cornered resource," etc.).