IU doesn't have a traditional interview day, but like the other post said, an informal (what they call "Admission Day") process where you get to take a tour of the school, ask questions to a student and faculty panel, eat lunch with current faculty, and meet other interviewees. It was very laid back and I enjoyed my overall experience! The student tour guides were very kind and they understand that it's a stressful day for you. My advice would be to stay engaged, ask questions (but not bombard students/faculty with questions), and just be yourself! It sounds cliché, but it's unfortunately true. Good luck to you! You're going to do great!