quick admin question re: bookmarking topics

How do I use the bookmark section of this forum? I see the bookmarks under "User Control Panel" and I see the little "bookmark" icon at the top left. When I click on it, there are lots of choices like facebook, twitter, gmail, etc. and it wants me to sign in. I am already logged into the forums. Can someone explain how it works. I've seen some great info and want to bookmark it so I can find it again. Right now, I can only find the ones I've commented on.

Thanks for your help with this newbie to forums.

Down in the blue bar at the bottom of the page you'll see a "Bookmark topic" option, and that's the one to use to bookmark a topic you want to be able to find again later. To see the topics you've bookmarked, go to your User Control Panel where you'll see a "Bookmarks" section (User Control Panel > Overview > Bookmarks) -- all your bookmarked pages should be there.

Thanks. I knew it had to be somewhere.