Open the Excel 2010 file that you want to make format changes to. Select the top-left cell in the range of cells that you want to change to the accounting format.

Excel for the web now supports conditional formatting, and the interface is easier to use than the desktop edition. Susan Harkins shows you how to use it.

How to create conditional formatting rules in Excel Once the custom value formats exist, you can apply them using conditional formatting rules. Right now, the format is set to General.