With TPD Image Watermarker you can digitally sign your work with either text and/or a logo watermark. You can place your watermark anywhere on the image, change the font style, color, size, underline, italicize, bold and many more options. It's up to you how you wish to customize it.
Once you're ready to watermark your work use the preview button to see how it will look before you save any changes. But don't worry, the program asks you where you want to save the watermarked work so your originals never get changed.