How to subscribe/unsubscribe from a thread made easy

OK...I'm posting this in the Beginners section because it's kind of a tutorial, but moderators please feel free to move it wherever.
I've seen many instances and variations of "replying just so I can follow this thread" posts since I joined so I thought I'd post this to make everyone's lives easier.
When you get to a thread go to the top and look for a little item called "thread tools". Click it; if you aren't already, you can click "subscribe to this thread" to follow the thread. Easy peasy, no need for posting or anything like that!
Email box getting full from being spammed by old thread followings? No problem! Do the above, but now the same option says "unsubscribe from this thread".
Cheers, mates!