What is the difference between a Coupon Code and Promotional Code?
A Coupon Code is applied in the shopping cart and usually a discount on the items being purchased during a certain time period. A Promotional Code can only be applied when creating a new account and is applied on every purchase you make (these discounts do change from time-to-time).
How do I use a coupon code?
Once you have added product to the shopping cart, go to the checkout page and choose the radial button "Use Coupon Code" (under "What would you like to do next?") and enter the coupon code (codes are case sensitive, so make sure your caps lock key is turned off). Then click "Apply Coupon" button, it should say "Success: Your coupon discount has been applied!" in a white rectangular box. Click anywhere out that box and continue with your checkout.