There are two different ways that you can add or update your payment information.
On goodeggs.com, you can edit your payment info on your Account page. You'll see this option under the Payment section.
On both goodeggs.com and the Good Eggs iOS app, you can edit your payment info during your next checkout. If you're new to Good Eggs, you'll be prompted to add payment info before you can place your first order.
On goodeggs.com, once you get to the Review & place your order page, you'll want to click on the CHANGE button next to the Payment section.
On the Good Eggs iOS app, once you get to the Summary page, you can click directly on the credit card info under the Payment section to edit.