How do I put my gicture into my membership details?

I guess the title says it all.
Having been here for quite a while now and feeling "at home" here , I'd like to put a picture to represent me when I write to the forums.

I cannot see how to do that

I guess if I created a new account the option would be in that process, but I couldn;t use my current member name in the new account, and I don;t want two.

Gaynor