You come back and check the thread/post in the forums periodically, to see what people post as responses/answers. Better yet, you get an account so that you do not have to post as a guest. Then, people will quote respond to your post and then you will be able to get a notification when such has happened, or you will get a notification for when someone posts in the subscribed thread. As a guest, I don't think AC would know where to send the notifications.