If you have a Shopify account, linking with Printhouse is easy. Please go to the "Storefronts" section menu and you will see the platforms available to connect with Printhouse.
Select the platform you use and it immediately redirects you to the page of your store, by just providing your web URL store (you must use a similar link like this http://STORENAME.myshopify.com). The platform will automatically ask access to Printhouse to link your inventory. Press “OK" and you're done. Your eShop account is now linked to Printhouse.