Complex sentence: She would wear it during the first part of the show, when reciting her more dramatic "Indian" lyrics; she would then change clothes at intermission, appearing in the second half dressed as a fashionable English lady to recite her more "English" verse.
Split into simpler sentences: She would wear it during the first part of the show, when reciting her more dramatic "Indian" lyrics. At intermission she changed clothes; in the second half, she was dressed as a fashionable English lady to recite her more "English" verse.