Click the 'View Blueprint' button:

This will display your site's blueprint, where you can 'Auto-Link' your Articles and Silos, or manually create links.  You can also print your site blueprint by clicking the 'Print...' button:

Clicking the 'Auto-Link' button will create standard Article-to-Article and Article-to-Silo links (where the last Article in a Silo links to the next Silo).  A dialog box asks you to confirm before continuing:

You can change these links manually by clicking on them, and choosing a different Article or Silo from the drop-down list: