This card requires no special configuration itself. Simply place on any page and it will automatically pull in all direct child pages. This card  should be added to a special section landing page where all child pages are the Location pages to be used in the directory.

Location pages can be of type 'group', which will automatically apply the Location card to the page template; or you can use any page type and manually add the Location card to the page's template. Be sure to fill in the address fields. The third line will be used as the drop down filter in the Location Directory card, so it is important to ensure that it is consistent across all locations (e.g. State, Province, Country). Be sure to also set a featured image for the directory.