How does Katniss's personality differ from usual during her interview?

Katniss is playing a role that she is not comfortable with. She is trying to endear both sponsors and the audience. Through the use of Cinna's strategy, she presents herself with charm and honesty, earning in the process both laughs and admiration from the audience. Her crowning moment is when she twirls in her dress and giggles endearingly. Katniss is much more quiet and pragmatic in real life.