When she is digging be sure to correct her asap using a stern voice, dont hesitate. Removing her from the cause is normally the best thing to do. Take her off of the couch and put her on the floor telling her "name & NO". Try putting her on the ground and giving her a toy or another treat to redirect her attention from the digging. Remember they are persistant little burgers and you will need to do this several, No tons of times before she really gets that you mean stop it and that you are not just playing.
Oh and vacuum the cracks of your couch !!
