If you are placing your first order, you can enter a discount code in the box on the final page before payment as shown below. Be sure to click 'Apply' once you have entered the code!
If you are placing a renewal, you can enter a discount code as shown below.
It is not possible to apply discounts to orders once they have already been placed, so if you forgot to add your discount code, you can cancel your order (find out how here) and re-order with the code, or contact our wonderful Client Success Team here for assistance.
Please note, that discount codes cannot be applied on auto-renewals, so if you have a discount code to use on your next order, you will need to disable auto-renew (find out how here) and place the renewal manually.