Using shortcut keys with the Ribbon

How do I use shortcut keys with the Ribbon UI?

Remember how you could use Alt keys with menus in previous versions of Office (e.g., Format, Paragraph was Alt+O,P)? On the Ribbon, each item on every tab has a keyboard shortcut associated with it. Press the Alt key to display a tip over each item. That tip identifies the unique key that will activate that item. As you press target keys, new tips appear for subitems. For example, Alt+P activates the Page Layout section of the Ribbon, then shortcut-key tips appear for commands on that section of the Ribbon, such as B for Breaks and N for Next Page section breaks.