Teaching yourself some simple keyboard shortcuts will cut down on mouse use and help to reduce the likelihood of pain in the hand and fingers of your 'mouse hand'.
A quick way in to learning shortcuts for Microsoft applications such as Word, Excel, PowerPoint, Publisher, or Outlook is to press and release the Alt key (to the left of the space bar). A series of letter codes will pop up on the Ribbon, and by using the keyboard to select the relevant code, a second series will pop up to take you to the action you wish to perform.
For example, to insert a row into an Excel spreadsheet, the sequence Alt H I R should be followed (try it!).
In Word, try Alt P O then the down arrow followed by Enter - this will select landscape orientation for the page layout.
There's a short video that demonstrates changing page layout using the Alt key sequence.
Teach yourself one or two at a time and you will quickly build up a repertoire of the ones you most frequently need.
A fuller list of shortcuts for Word 2010.
Use the internet to search for shortcuts for the software you use. A good place to start is at www.shortcutworld.com