Once you have a basic watch face put together, letting the user customize both the appearance of the watch face and the information shown on it, helps make the watch more personal and more useful.
For personalization, use UserConfigurations to allow the user to
tailor the appearance. For customizing the information shown, include support for Complications.
For both types of customizations, the user uses the Watch Face Editor to make changes. To enable the editor, set the watch face to be editable (see the packaging guidance for more information).