How to: Modify the default style.
Solution:
Select 'Style...' from the 'Format' menu to display the 'Style' dialog box. Select the default style 'NORMAL'. Click 'Modify...' and make the necessary changes in the 'Format Cells' dialog box.
1) Select the 'Format' menu and select 'Style...'. (The Style dialog box appears.)
2) (Optional) Select 'NORMAL' from the 'Style Name' drop-down list.
NOTE: Excel selects the NORMAL style by default.
3) Click 'Modify...'. (The Format Cells dialog box appears.)
the Modify... button
4) Do one or more of the following:
a) Click the 'Number' tab to change the default numbering format.
b) Click the 'Alignment' tab to change the default vertical and horizontal alignment for cell contents.
c) Click the 'Font' tab to change the default font attributes for cell text.
d) Click the 'Border' tab to change border settings.
e) Click the 'Patterns' tab to change the background color and pattern for cells.
f) Click the 'Protection' tab to change the appropriate protection method for cells using this style.
5) Click 'OK'.
6) (Optional) Clear the appropriate check box to exclude the corresponding format from the style definition.
7) Do one of the following:
a) To apply the changes to the selected cell(s), click 'OK'.
b) To change the style without applying it, click 'Add' and then the 'Close'.