If you would like to add a text or image watermark to Microsoft Word document (single page or all pages), customize the font, layout, etc. see this post.

How to Insert a Custom Watermark You can also create personalized watermarks using text or images that align more closely with your intent.

You may already be adding your "John Hancock" as an official sign-off to your business stationery, but one more layer of customization is done through a watermark. This image or small block of text ...