Customize Navigation view

If you create a navigation structure in Navigation view, you can customize how that structure is displayed.
To Do This
Zoom in or out Right-click the view background, point to Zoom on the shortcut menu, and then click the percentage that you want to zoom in or out.
Automatically size a large navigation structure to fit into the view Right-click the view background, point to Zoom on the shortcut menu, and then click Size to Fit.
Change the orientation of how the structure is displayed Right-click the view background, and then click Portrait/Landscape on the shortcut menu.
Expand all of the subtrees (the pages below a parent page)  so that you can see the entire navigation structure Right-click the view background, and then click Expand All on the shortcut menu.
View only the pages in a subtree  Right-click any page in the subtree you want to view, and then click View Subtree Only on the shortcut menu.