Change the format of a cell
You can apply formatting to an entire cell and to the data inside a cell—or a group of cells. One way to think of this is the cells are the frame of a picture and the picture inside the frame is the data. Formatting the cell might include adding a border, adding color or shading, and changing the size or style of the cell.
Apply Excel Styles
Select the cells.
Select Home > Styles and select a style.
Modify an Excel Style
Select the cells with the Excel Style.
Right-click the applied style in Home > Styles. Select Modify.