By far, the format painter is one of my favorite tools in Microsoft Office. It is very easy to learn. But before I explain the steps to making it work, let me define what it does. The format painter will copy the format from one part of your document to another place. For example, it could help you quickly copy a sub heading format in a Word document to other sub headings in the document. In Excel, it could copy how a particular cell range looks onto another cell range (even using multiple worksheets at a time). So the format painter looks like a tiny little paint brush.
To make it work, first select some text to you would like to copy-cat the format to other locations in the document. Then click the format painter which is in the clipboard group of the home tab (Office 2007 or 2010). Upon clicking the format painter button, your mouse icon will display a paint brush. Drag or click onto the text you would like to copy the formats to.
TIP: If you have a lot of formatting to do, double click the format painter so that you can use it as long as you need. Make sure when you are finished with its use, that you eithor click the format painter button or hit ESC to turn it off.