Excel 2010, like the Office versions before it, has a lare number of built-in keyboard shortcuts that let you choose any Excel command without removing your fingers from the keyboard. The most common Excel commands have always had Ctrl-key shortcuts (such as Ctrl+S to Save), and those shortcuts still work. But now you can use keyboard shortcuts to access uncommon Excel commands.
Place the cell cursor in the proper location (if applicable).
For example, if you want to use the keyboard to apply formatting to specific cells, select those cells.
Press Alt.
Shortcut letters appear on the Ribbon and numbers appear on the Quick Access toolbar.
Press a letter to select a tab on the Ribbon.
For example, press P to select the Page Layout tab. Excel displays the tab and letters for each command on that tab. For example, pressing P pulls up the Page Layout menu on the Ribbon.
Press a letter or letters to select a command.
Excel displays options for the command you selected. If you pressed the wrong key(s), you can press Esc to go back one step at a time.
Press a letter or use the arrow keys on the keyboard to select an option.
Excel performs the command you selected, applying the option you chose.