There are two ways to see if you are currently subscribed to a document or discussion. The first way to see if you are subscribed is to enter a document category and view the listings within the category - any documents/discussions you are currently subscribed to are indicated by a small green tick, located on the icon of the document/discussion listed.
The second way to check if you're subscribed to a document or discussion is to enter the conversation area (by clicking on it) and viewing your current subscription status (located above the comment box). You will see an indicator displaying the word ‘Unsubscribe’ with a green tick next to it if you are currently subscribed to this conversation.
This option will display the text ‘Subscribe’ and appear ‘greyed out’ if you are not currently subscribed to the conversation - if you wish to follow the conversation, just click on this option to begin following it and begin receiving notifications.