Please refer to CATESOL page about how to subscribe –
The method for subscribing to a list is to send a blank email to “listname”-email@example.com. Substitute the name of the list, such as “tell” for the word “listname.” For example, to subscribe to the Technology Enhanced Language Learning Interest Group list, send a blank email to firstname.lastname@example.org.
The method for un-subscribing is the same as above except you should substitute the word “unsubscribe” for the word “subscribe” in the directions above. For example, to unsubscribe from the Adult Level list, send a blank email to email@example.com.
Note that both the “subscribe” and “unsubscribe” commands must be sent from the email address that will be/is used on the list.