BONUS! We put this in as an addition, because right around the time we were making the ThePrintful/Shopify integration, Facebook opened their own store allowing people to put a totally decent shop that could link to any item from any store you are using!
What does this mean?
It means that if you have stuff you like from any of your shops, be it Rageon, Society6, Spoonflower, etc, you can collect them all in one place on your Facebook Page (not your personal page). That is a huge deal, and should be your first option before you make the leap to a serious web presence with white-label branding and a larger, more focused shop.