It can sometimes be easy to overlook the alternate shipping address procedure during checkout. When you get to the shipping address page, make sure to enter an accurate billing address that matches the payment method. It will be checked for security reasons. To ship it to a different address you can add the address by clicking the link found below nex to the red bar:
When you click that link you will be directed to this page. After filling out the shipping info below, click the circled floppy disk icon in the top right to save.