To apply a Discount to a Receipt:
Select Options at the bottom of the screen. Then on the Receipt Option screen select Discount.

The Discounts window appears, with all discount options available.
Note: Options for Open Item and Open Receipt will appear here if they're configured.

Select a Discount by tapping on it. That Discount will be applied and appear on the Order screen, below Subtotal and Tax.
Note: for more information on how a Discount will be applied, see the Discount related articles in the Knowledge Base.

Note: Only Employees with the proper Role and Permission settings have access to apply Discounts. Other Employees must provide a Manager’s PIN to apply a Discount.