Uploading or changing profile pictures is quick and simple. Click on "Upload Photos" in the drop-down menu in the top right-hand corner or "Upload pics" below the status box on your profile.
You can upload photos there and then decide if you'd like to use them as your profile picture.
All uploaded photos can be found under "my photos."
Hovering over one of the photos in your photo folder will show 3 icons. Click on the left icon to select that photo as your profile picture.