Help adding my picture to AW signature (you need 50 posts to select custom avatar)

I'm hoping this is in the correct room...can anyone help a tech-disable writer add her profile picture to the signature everyone sees when I post a comment? I see many people put an avatar under their name and some seem to have real photos of themselves. I've uploaded a picture from my web site and would like others to see this picture when I comment on the boards. Thanks in advance for your help.

Thank you! Had no idea.

Thank you. Will do.