In order to redeem a Mighty Ape gift voucher, you need to login and enter the voucher codes here:
Simply, enter the code from the bottom of the gift voucher and click 'Redeem Voucher' which will add the gift voucher as credit to your Mighty Ape account.
Your account credit will be valid for 3 years from the date of redemption.
To use your account credit, simply stay logged in and go through adding products to your Trolley as normal.
When you get to the "Payment" step of the Checkout, there is a check box at the top of the page that allows you to use your account credit against the order. If the value of your order exceeds the balance of your account credit, you will be invited to add a credit card or select another method to pay the remaining balance.