I must plead nescience about bookmarks. Is that the same as adding it to the favorite links?
At the top of every thread, in message 1 is a line that says: Bookmark Report Abuse.
If you click on Bookmark, it will offer to add it to the bookmarks on your public profile (a/k/a your Freeper homepage). If you hit the other one, sometimes you get viking kitties, sometimes an irritated mod.
If you go to your Freeper homepage, you will see on the top several things to click on. One of these is links. Those links are the links from threads you have bookmarked.
Now you can add threads to your regular browser bookmarks too. If you are using IE, you add it to your favorites. That way, you wouldn't have to be in FR to get to it.
hope this helps!