Upon checkout, you will be prompted to enter your gift card under the "Payment" section. Underneath "Pay with a Credit Card" and "Pay with PayPal" you will view an option that says "Redeem a Gift Card". Once you click on "show" your 16 digit gift card number can be added and applied.
You can also check your Gift Card Balance to ensure you have enough funds available to place your order. If your card is not applying, please contact us at 1-800-875-9453 and we would be happy to look into this for you!