Select the card that you want to add the Chatter capability
Selec"Preview":
Notice that there is no Chatter feature:
Go back to the card menu and select "Edit Card" :
Select the toggle for Shuffle Chatter :
Then select the check mark to save the card:
Select "OK":
In your preview you will see that the "Chatter" feature has been added the select "Finish":
See this in action on our Shuffle by Elify YouTube Channel: