After you have created a Story, you might want to publish and embed it on an external website. You can easily do this after clicking "publish" in the upper right corner of the editor. You will then be presented with the publish settings. After selecting to publish your Story you can find the blue square containing "share by link" settings.

pressing the embed button will show you the iframe html component that you will need to copy to the external website where you wish to embed your We Are Story.