To Insert a Menu Separator

1. From the Mac OS menu bar, click Tools menu Customize Interface (CUI) or at the Command prompt, enter cui.
2. In the Customize dialog box, on the Menus tab, under Menus List, expand the Menus or Shortcut Menus node and the menu, then select the submenu or menu item after which to insert a separator.
3. Click the Options action menu below the Menus list, Gear icon, and click Insert Separator.