Posted: 06/10/2014 at 11:40
Go into your Settings page - and then into Forum Settings. That will give you the option to be notified of replies.
Also, if you scroll down to the bottom of a thread you'll see a little tickbox on the bottom lefthand corner which you can check to receive notifications.
However, there have been some technical blips on the site and I think some people don't get notifications even when they've asked for them. The tech team are working on the blips, and there are future plans to re-vamp the site.
I don't bother with notifications - I get more than enough emails anyway. I just check the forum every so often.
Hope that helps