If your online store runs on WordPress with the WooCommerce plugin, Print Science offers a free plugin that connects your store to the Designer server — no custom programming required. It launches a Design Online session from a product page and returns the customer to checkout once they've finished personalizing.
WooCommerce is currently the only actively-supported shopping cart plugin. If you use a different shopping cart, see Plugins not supported for previously-supported carts, or the API to integrate a cart yourself.
From your customer's perspective, the Designer is integrated smoothly into the standard purchase flow. This video shows a customer using the Designer in a WooCommerce store:
See also