Grouchy, you have to ask someone under 20 years of age on how to attach pictures (which are too large a file to attach the traditional way).
It involves signing up to a photo site and linking it to this site, which is an effort unless you plan on doing it more than once. There are other ways as well, which makes it more confusing; as 2 people will describe 2 different approaches. One leaves a link that you press and it takes you to a seperate site where the photo is displayed, and the other puts the photo right in the text that you put on this site.
Find someone you know / like / trust to guide you through the easiest one, and you will probably evolve to the slick presentation that appears directly here, in time.
One of the problems with learning this stuff is the fact that a lot of it defies intuition; and most "how-tos" have huge gaps in the information, and miss a lot of the steps you will have to wade through.
Maybe on this site there could be instructions on how to load pictures and create your avatar, and it can be edited and added-to, until it is useable by someone on the first try. A sort-of wikipedia approach to getting something workable. The reason there is not one on here now is because it is quite a hard task to present the method in a way that can be understood in a first-try situation.
It could be in its own category near the banner.