As you publish various projects, it is important that you take credit for all you do. You can definitely add a watermark to prevent theft, but even if you are sharing in a "safe" environment, you might want to add your signature. Let's see how you can do that.
watermark
How to add watermarks to your images
You take fantastic photos, you create great montage, you design memorable scrapbook pages. You deserve the credit, or at least the safety of knowing nobody will take your work and claim it as their own. In the world of internet, it is so easy to grab a photo without permission, so how can you protect your work? With watermarking. Although watermarking is often used to protect the work from being used elsewhere, it can also be used simply as a signature too.