Expertise: I currently run a high performing referral channel with several million invites every year.

As you build out your growth strategy it’s important to identify the main “macro” conversion. This is an action that you need users to take to make the product successful.

In your case, the product goal is - get multiple people to commit to buying a single product. On the other side of this, your customer’s goal is - to get a deep discount on a product.

On the surface it would seem that the more comprehensive way to get users to invite others to your service is to get them to go in on buying a product together. This would mean that you want to build your growth features around sharing product pages.

However, one might consider that while friends and family might be buying same offer for things like food, activities and experiences, they might not be willing to buy the exact same shoes, dress or pants.

That said, you seem to be on the right track with the referral link plan. The key to getting people to invite others is to clearly showcase the functionality and benefits.

a) Triggers - you need multiple placements from which to invoke the invite flow.
Product page to display -10% price with CTA to share ("Get this product for 10% by inviting friends)
Home page (“Make your next purchase 10% by getting your friends to sign up and buy”)
Emails promoting the program.

b) Landing page that clearly explains the program (“Get $30 to spend when your friends join and buy”)

c) 2-sided benefits, consider clearly offering something to the invitee other than your great group buying prices (“Invite your friends and you both get 10% off your next purchase")

On the technical level for Facebook sharing you might want to consider Messenger vs. Wall Posts. While you might think that you’re getting more reach with a wall post, consider that Facebook algorithm is not very kind and your shared post might not get seen much. Direct messages on the other hand are user-to-user. They have a very high likelihood of getting opened and lead to much better clickthrough.

This might be quite a bit to build on your own and you might want to experiment with a service like Extole. I haven’t used them myself, but I’ve recently reviewed their offering and it seems like a good way to get a new referral program started.

Lastly, don’t discount email invites. They still perform really well in terms of engagement and can be fairly simple to set up with a mailer and a well optimized template.

Most important - figure out what kind of numbers work for you. It’s easy to get a referral program get out of hand in terms of cost if you’re finding that your payback period is of significant length.

Feel free to schedule a call if you would like to discuss further.