Do you see the little guy in the bottom left corner?
His name is Logo.
Creative aren't I?
I'm going to use him to put watermarks on my photos and sketches that I put on here.
Look, here he is again!
Do you see him?
Allright, here he is big!
Edit: Some more info. How to make a logo and turn it into a watermark...
I used mostly these 2 links to figure it out. I've never used illustrator before so it took me a while to figure out how to do anything. It's so different from photoshop!
this had some helpful basic illustrator stuff:
and this was very useful to learn about watermarks: