You have to be viewing an ad in the Classified section.....whether buying or selling doesn't matter, or it won't work.
Click on "Feedback Score: reviews" in the members avatar on the left side of your screen.
That will open a new page and just below the heading you will see a link that says "Submit Feedback For _______"
Click on it....
From there you can see a place to copy/paste the URL link from the thread you sold or purchased from and submit a comment about your purchase. If you don't know how to copy/paste, just type the "http://www.forabodiesonly.com/" stuff from the very top of the page you're viewing.
I hope this helps....it is a bit confusing and takes some practice :cheers: