To add a common watermark such as DRAFT, CONFIDENTIAL, or DO NOT COPY to your document,
Under Design, in the Page Background group, click Watermark.
Scroll through the watermark gallery and click the watermark you want. The gallery includes horizontal and diagonal watermarks for Draft, Confidential,Sample, ASAP, Urgent, and Do Not Copy.
Word automatically applies the watermark to every page except a designated title page.
If you don’t see the watermark applied, click View > Print Layout. This also shows how the printed watermark will look.
If you’d rather create your own text watermark, at the bottom of the watermark gallery click Custom Watermark , then click Text watermark, and in the Text box, type the text you want. You can try different fonts, layouts, sizes, and colors while you’re at it.