To add a 'Shop' button to your page:
1. Click + Add a Button below your Page's cover photo if there already isn't a button there already (if there already is a button there, you can edit it via a context menu that drops down when you hover near the button)
2. Select the Shop button and let it link to your Shopitag pop-up shop. You can also directly integrate your Shopitag shop into your Facebook page.
3. Click Add Button.
4. Once the button has been created, you can test your button by hovering over it and selecting Test. From your menu under your cover image, you can also select to view your page as a regular visitor (instead of admin) to do an additional test.