You can reward members with a discount code only they can use. It works by limiting a Shopify discount to your members, using the customer tag Single adds to each member's Shopify profile.
How to set it up
In Shopify admin, go to Discounts and click Create discount.
Choose Amount off order, and set the method to Discount Code.
Name the code, like
MembersOnly.Set the discount value and any minimum purchase.
Under Customer eligibility, choose Specific customer segments and select the segment for your members. Single tags each member's Shopify profile, so you can build a segment from that tag.
Set a start date of today and leave the end date blank for an ongoing discount.
Click Save.
Share it
Tell members about the code. Only active, logged-in members can use it, so you can post it anywhere.