The 25-year-old Bollywood newcomer made her Cannes red carpet debut as the face of L'Oreal India.
She accessorized with white Ferragam peep-toe heels, Chopard stud earrings and a statement Amrapali cocktail ring on her left hand index finger.
Her hair was styled in an updo with a curly bouffant top.
Her enchanting smoky eye makeup, by the L'Oreal France makeup artist Rie Omoto, included L'Or, L'Or, L'Or gold eyeshadow and highlighter riding right upto her thick and arched eyebrows; and silver eyeshadow on the inner corners of the eyes and under the lower lashes. The look accentuated and emphasized her chiseled features rather than the color itself.
Nude lip gloss, fuchsia blush and gun metal nail polish rounded her mesmerizing looks.
Explaining the use of gold, Rie said, "Gold is a transformational color that can take a woman from day to night and back again by simple adjustments in its application and blending." Sonam walked the red carpet with Chinese actress/singer Fan Bingbing who looked a princess in an ombre violet Atelier Versace strapless gown. The elaborate gown had a fitted bodice and chiffon ruffles on the skirt.
Sonam later attended the after party in shaded net and silk polka dot sari with a shirt inspired backless blouse, by young Indian designer Masaba Gupta.
Sonam has had a busy time meeting press and shooting for the makeup brand since she set foot in Nice.