In Microsoft Word 2007:
  1. On the Office ribbon, select the Insert tab.
  2. Under the Text group, click Quick Parts, Field.
  3. Under the Categories box, click Date and Time.
  4. In the Field names box, select CreateDate, PrintDate, or SaveDate.
  5. Select the date and time format that you want in the Date formats box.
  6. Click OK when ready.

In Microsoft Word 2003 or prior:
  1. In Microsoft Word select Insert, Date and Time from the menu bar.
  2. Select the appropriate date format and click OK.
  3. Mark the Update Automatically checkbox to have the date be the current date every time the document is opened.