1): Get the pic you want to post on your screen
2): Scroll down and click "Show in Blog or Forum"
3): Four options appear in boxes on left. Go to third one where it says "UBB ports for all forums" and right click
4): Click copy
5): Go back to forum and find the topic you want to post the pic in
6): Scroll down to where it says "New Comment" and click
7): Place the cursor in the box and click "paste" and if you want to write something then do that too once the pic has been pasted.
: Then click "Submit Comment" and bingo! Your pic should appear in the topic on the forum.