You will need an ICONIC account in order to redeem your Gift Card. Log in to your account (if you don't have an account, you can create a new account), add the items to your bag, and in the checkout, enter the card number or code into the ‘ADD VOUCHER OR GIFT CARD’ field and click 'Apply'.
Any remaining value will be stored under the Your Credit section for you to use on future purchases (valid for 12 months).
Don't want to use your Gift Card now? You can redeem your Gift Card under the Your Credit section of your ICONIC account and the credit will automatically to your next order.