Recipe: buy one, get one free
Goal: a free Left hand mixer knife with every Right hand mixer knife purchased.
Create a new discount, name it, and set Type to Buy X, Get Y.
Leave Stop Processing Further Discounts off, so customers can still earn other discounts.
Give the group a Discount Name.
Under Customer buys, set the quantity to 1 and choose the Right hand mixer knife.
Under Customer gets, set the quantity to 1 and choose the Left hand mixer knife.
Set the discount to Discount a percentage at 100, which makes the second knife free.
Leave Apply repeatedly on, so the reward is earned once per trigger product. A customer buying 4 right hand knives gets 4 left hand knives free.

Add any messages you want the customer to see when they qualify.

Where to go next#
- Cart Actions, how the reward quantity is worked out when the trigger and reward are the same product.
- Messages, the tokens available to a Buy X, Get Y discount.