How to Use Gift Cards on Decathlon Website and App Step 1: Tap the cart icon. Step 2: Confirm your order, delivery address, and proceed to the “Payment” step → select “Gift Card.” Step 3: Enter your gift card number and PIN, then press “Add.” You can add multiple gift cards if available. Step 4: Enter the amount you want to use from the gift card, choose your payment method, and complete your purchase. (*Note: A gift card can be used for multiple orders if there’s remaining balance.)