Hi. I’m a PC. If you’re a mac, you should have a program on your computer to do this. I don’t know what it is or how to use it. If you’re a PC, this tutorial is for you.
Download Photoscape. It’s free. It’s easy to use. I like it a lot. Open it up. You can go into the batch editor (and watermark all at once) or you can just edit one at a time. I like to do it one at a time because then I get to choose where the watermark goes on each picture. Choose your file on the right side that you want to watermark.
To watermark using TEXT only (easiest):
From there, click on the “object” tab.
Under this tab you’ll see a “T” in the second row down. Click on that and it’ll bring up a menu bar like this:
In the blank area, fill in the text you want to watermark with. You can use the name of your blog, your initials, (probably stay away from racial slurs), etc. Choose a color that isn’t going to compete with your photo. Most of the time I choose white. Just for kicks, I chose yellow this time. I like to live it up. Then I play with the opacity a little bit. You don’t want the watermark to be too too noticeable, just enough that people won’t steal your photos and use them for evil. When you like the way it looks, click “ok”. From there, you can use the arrows on the sides to size it down where you want and drag it to wherever on the picture you want. Click “save” and you’re done. Easy, yes?
To Watermark Using An Image:
It’s basically the same process, you just click on the little mountain and sky image on the first row. Go to the top and click on “photo.” Make sure your watermark image you are going to be using is saved in a PNG file (you can use any illustrator program for this) and that the background is TRANSPARENT. It’ll end up looking like this:
aaaaand you’re welcome.
Lexi Mag 
Done! Yay!!! Now if I could only figure out your tabs tut. That one will have to wait for another day. Thanks again!
I was JUST thinking I wanted to do this to my photos and wondered how. Thank you!
One day, I will come back here and actually write this down! thanks!
This is so random – THIS is where I learned to watermark my photos! I googled and came up with your blog. Huh, who knew? I was just clicking through your "blog design" category (cause my design needs some love, but I'm lazy) and realized, hey, this is where I learned to watermark!