Go to the eBay website and click the "Sign in" link. If you do not have an account you can sign up for free by clicking the "Register" link.
Enter your username and password when prompted. Click the "Sign In" button to go into your account.
Click the "My eBay" link on the top right hand side of the screen. Go over to the "Won" section, which is located in the bottom left side of the screen. In this category, you will see all of the items you won in auctions or purchased outright.
Click the product you want to pay for by clicking on the product page.
Click the "Pay Now" button on the product page. Enter your Paypal username and password when prompted. If you do not have a Paypal account, you can register for free on their website. After you do this, the next page you will see is the eBay checkout page.
Go down to the category entitled "Redemption Code." Enter the eBay gift card code on your card or from your email. At this point, your eBay gift card should be activated.
Click "Apply" and "Update Total". Confirm your shipping and billing address as well as the order itself and confirm the total.