The daughter of American author Danielle Steel, Traina grew up in San Francisco before moving to Malibu to attend Pepperdine University. Early in her career she interned for Carine Roitfeld at Vogue Paris and subsequently moved to New York where she assisted stylist Marie Amelie Sauve. Traina has modelled for brands including Louis Vuitton and became a Chanel beauty ambassador in 2009.
Traina is executive creative director of Assembled Brands, the holding company founded in 2013 by Adam Pritzker to develop emerging fashion designers. In 2014, the company launched e-commerce venture The Line, followed by The Apartment by The Line, a New York showroom in which lifestyle products curated by Traina are laid out as if in a private home. A second Apartment is located in Los Angeles.
Traina is also a creative consultant and has worked with clients including Balenciaga, Altuzarra and Erdem.