Excel - Shade Alternating Rows

Making alternate rows go from white to shaded and back to white is a pretty quick job once you know what to do.

1.  Select the cells you want to add alternating shade on
2.  On the Home Ribbon click the "Conditional Formatting" button
3.  Select "New Rule"
4.  Among the rule options select "Use a formula to determine which cells to format"
5.  Type in the formula "=Mod(Row(),2)=0"
6.  Last of all, cluck the format button and select a color you want to use for the alternating cell shading.

Option 2, you can also use the "Format as Table" button next to the "Conditional Formatting" button on the Home ribbon.  This has all sorts of other built in functionality that goes way beyond just alternating shading so I don't use it that much.

Microsoft Instructions on how to create alternate cell shading...