Just be nice, friendly, and presentable. Appearances do matter since it is an Asian beauty store, though you don't need to have perfect skin or a super stylish look. The main questions are how familiar you are with the products/brands and what times you're available. Easier for college students since they prefer all day on weekdays (no part-time there) and doable for high school students if there's a weekend availability. Make sure to check if the interview is in Stonestown or Japantown.