These are instructions on adding a signature and avatar that will appear below and beside all of your posts.
Click "profile" under the banner above, then click Modify Profile, then scroll down and you will see that it says signature and you will also see avatar.
In order to upload the signature or avatar. You have to save the picture you want, then go to either www.tinypic.com , www.imageshack.us , or your photobucket account. Then upload the picture, and copy the code if it is a signature. If you are putting an avatar, then copy the URL. Then paste it onto the space it gives you.
After your done all that, scroll down and click save changes, and ta-da your done!
If you still have any questions, feel free to ask here.
P.S - i have also added sample avatars. So you may choose one of the avatars on the list of avatars! (: