Specifying cell fill patterns and colors

In Design mode, right-click the cell or cells to format and select Format Cells.

Click the Pattern tab.

You can choose a pattern for the background of a cell. The Primary color specifies the color of the background, and the Hatch color the color of the pattern.
Note: On the Pattern tab you can apply a background color to one or more cells. But you cannot apply a background color to all spreadsheet cells. To apply a background color to all spreadsheet cells, or to insert a background image, select Format > Background.