You can amend your order as long as it hasn't entered production. Log in to your account, go to Orders and select 'Amend Order' if the option is available.
To aid you, click the help button in the bottom-left corner of the screen and choose 'Amend an Order' to launch our guided tour.
As we work to quick turnaround times, items are printed soon after your order is placed. If the option isn't showing, your print may already be in production and can't be amended.