First, you have to click on the Payment tab from the left side, Click on the Coupons from your top address bar and then click on Create the coupons. #
2. In Rules: #
Set your coupon name.
Add code type for your customer.
Add coupon code.
Select the currency type in which wanna discount your customer.
Select the type of discount.
Set the amount of discount rate.
3. Next is: #
Set a time limit for coupons.
Set reusable limitations for customers.
Set order criteria for your customers.
Set the value of reusable coupons for customers to another product or not.
And last, Set descriptions from your customers.