You see "Quick Links" on the blue bar near the top of the page?
Click that and select "Edit" - there are three options, it doesn't matter, this is just a short cut.
Once you are taken to the next page, on the left there is an option for "Edit Avatar". Click that.
Once you are there, you can select to browse your pictures for an image, upload it, hit save and you are now a member of the cool kid club.
PM if you need some help.