Up in the right corner of the screen, there should be a link that says "edit profile", click on that. Once you are in there, click on the little tab that says "avatar". You can then click on the browse button and look in the files on your computer. Once you have found the picture you want, double click on it and then hit the update button, it should pop it in for you. Don't forget to save!
Hope this helps!
-Tzeitel
Psalm 73:23-28
23Nevertheless I am continually with You; You do hold my right hand.
24You will guide me with Your counsel, and afterward receive me to honor and glory.
25Whom have I in heaven but You? And I have no delight or desire on earth besides You.
26My flesh and my heart may fail, but God is the Rock and firm Strength of my heart and my Portion forever.
27For behold, those who are far from You shall perish; You will destroy all who are false to You and like [spiritual] harlots depart from You.
28But it is good for me to draw near to God; I have put my trust in the Lord God and made Him my refuge, that I may tell of all Your works.