I'm the last person you need to change your avatar/sig for. I just don't think a friendship between us can work out due to the obvious point of disagreement and lack of other interaction to make me think this could work.
Ok thats easy at the top left corner of the page you will see
User CP click it.
Then on the left side of the page the first box says Your Profile click
Last their are blocks and at the bottom of each block it says
you put the url their and bing your done. Dont forget to save changes also.
Remember that each block fills a precise background on your profile such as main, block borders, main borders, and etc.