Excel 2010 has various predefined conditional formatting styles and rules which enable users to apply styles, formatting and rules instantly on the specified data cells but sometimes it becomes frantic need to apply formatting and style over spreadsheets. For this Excel 2010 has an option to create a new conditional formatting rule which eventually abets users to mark out data cells in desired way.
Launch Excel 2010 spreadsheet on which you want to apply rule.
Now select the spreadsheet portion on which you need to apply rule, navigate to Home tab and from Conditional Formatting options, click New Rule.
From New Formatting Rule dialog, under Rule Type, select Format only cells that contain and from under Format only cells with options select Blanks, as shown in the screenshot below. When done, click Format.
Upon click, Format Cells dialog will appear, now select the Pattern Style and Color, to mark out blank cells in your datasheet. From the left side you can select different colors for the selected pattern. Navigate to different tabs and to change the Font, Border for the blank cells. Now Click OK.
It will bring you back to the New Formatting Rule dialog, here you can see the preview of the changes made. Click OK to mark out all the selected cells with specified formatting styles.
You will see all the blank cell filled with the specified formatting style, as shown below.
For editing the rule you can always go to Conditional Formatting options and hit Manage Rules.