Once you have created the order click on the Options Button.
In the options screen, click on the Smart Coupons button.
The coupon screen will appear with a list of applicable coupons and promotions. If the items in the virtual ticket do not meet any criteria of the coupons you have setup then nothing will show in the list.
Select the coupon that best applies to the order you've placed. The order will update with the new total.