Most sources I found explained it really easily, but you had to implement the code it your layout. However, the code cannot be implemented in all layouts. Some other sources only added the signature to new posts. I didn't like this one because it wasn't on all my posts, but then for some unknown reason the picture didn't show up on my posts. It just showed up as a block with a question mark in it.
Today, I found this post by Cody it Pretty that allowed me to implement my signature in one easy step. Well, only one step if you count the fact that my signature was already uploaded on an online picture storing website. I use PhotoBucket, but she also recommends using Picasa Web Album.
What do you think of the signature? I'm not sure if I like it. So, it might actually change up again so, but let me know what you think.