When you have a document in PDF format adding a watermark of yours to the background could come handy as ornamental or as asserting your ownership. This creative common tool can do it for you in a minute without putting an extra cash for it.
File:Add-Watermark-to-a-Pdf-Document Step 5.jpgDecide for the font color, font size and style and opacity of your water mark. Also, decide for the position and angle of the water-mark text on your page.
File:Add-Watermark-to-a-Pdf-Document Step 6.jpgSimilarly, you have options for the image you put on the document. (If you use a one page blank pdf document the image will be converted to a PDF document, optionally.)