At the beginning of the masterclass, Professor Fried talks about the general character of the piece and comments that the Nocturne is based on color. In the Tarantella, she remarks the importance of the accents to show the suitable character: powerful and Spanish (like 'zapateado').
It is advisable to pay attention to the composer's clues but the performer has to create the atmosphere, their task is to explain the meaning of the music, not only with the notes but also with the body language.
She explains the phrasing, the expressivity, bow speed, dynamics and so on, and makes a reflection about the purpose of every note: those whose function is decoration and others with more structural role. It is important to have in mind and to use all the musical aspects which conform the character of the music.