1. Press [Ctrl][F3].
2. Enter DateStamp in the Names In Workbook text box.
3. In the Refers To text box, enter the following formula:
=TEXT(TODAY(),"d-mmmm-yyyy") & " " & TEXT(NOW(),"h:mm AM/PM")
4. Click the Add button and then click OK.
Now you can add a time and date stamp to every worksheet in your workbook by typing =DateStamp in any cell.