Hello,
You can rearrange the order of which the coupon is displayed in the order total. If you login to your admin area, go to MODULES > ORDER TOTAL.
From there, you will see Discount Coupons, Total, Low Order, etc. You need to order these items numerically to display properly. For instance, in one of our stores, we have the order as:
SUBTOTAL (1)
DISCOUNT COUPONS (2)
SHIPPING (3)
TAX (4)
TOTAL (5)
You can edit the order by selecting the item and editing it. Just change the value in the "Sort Order" field.
Hope this helps? Good luck!
:)