YSL's UK makeup artist Fred Letailleur loves the YSL All Hours Foundation (£36): "It has medium coverage, lasts for 24 hours, and feels completely weightless." Letailleur recommends setting the foundation with a light dusting of powder for a true matte finish. For extra-oily areas, he recommends the Nu Blotting Lotion (£27), which can be used under or over makeup to control shine without dehydrating the skin.