To review and change the properties of a stamp:

  1. Select the Hand tool on the Edit toolbar
    or the Stamp tool on the Commenting toolbar (View > Toolbars > Commenting).
  2. Right-click on the stamp and choose Properties.
    Change the appearance of the stamp as well as its opacity – handy if you want the page's contents to show through. The Appearance drop-down menu will only show built-in stamps, but no user-defined stamps.