First, create your custom watermark.
- On the Design tab, select Watermark > Custom Watermark.
- Choose Picture Watermark and select a picture, or choose Text watermark and type your watermark text in the Text box.
- Click OK.
Next, save the watermark so you can use it in other documents.
- Double-click near the top of the page, to open the header.
- Move the cursor over the watermark until the cursor displays a four-headed arrow, and then click the watermark to select it.
- On the Design tab, in the Page Background group, choose Watermark.
- Select Save Selection to Watermark gallery.
- Give the watermark a name, and click OK.
To insert your custom watermark in another document, select it under General in the gallery of watermarks.