That's a great question. In this forum, the action you're describing is called "Subscribing". When you're in an actual topic, look at the very bottom left corner. You should see 3 icons. The 1st is the typical RSS Feed Icon, the next is a little red flag ...when you mouse over the red flag, a pop up window will say "Subscribe". Left Click on the little red flag subscribes you to that topic. Hope that helps.