Schiffer said that she was popular in high school, but felt socially overshadowed by the other girls in her class. She has revealed that because she was so tall, she became very shy and did not want to be noticed. She was also subjected to jealousy by others as she came from a wealthy family that was well-known locally. Schiffer became fluent in English and French.
She originally wanted to become a lawyer and used to work in her father's law firm. She later dropped these aspirations when, in October 1987 at 17, she was spotted in a nightclub in Düsseldorf by Michel Levaton, the boss of Metropolitan Model Agency who signed her up to become a model.