The way Joomla works is that Itemid is always associated to a menu (it's actually the menu's id).
So if you create corresponding menus, the Itemid will be added automatically, and then kept by CB, except when going to user profiles where it will be finding the CB profile menu's itemid automatically.
If you need Itemids (e.g. for links) but don't want corresponding menu item to be visible, add a menu and put into an invisible position.
Hope the above is understandable. Joomla documentation on itemids might help there too.
Hope I understood correctly your request. If you think it's not the case, please clarify and give exact example.