If your skin is in constant need of hydration, consider trying the L'Oréal Paris Pure Hyaluronic Acid 7 Replumping Ampoules ($25), a seven-day treatment that helps reduce fine lines, locks in moisture, and makes your complexion look as soft and supple as Botticelli's muse. Crack one open in the morning and use about half the serum allover before makeup application. To preserve the other half for your nighttime routine, simply invert the cap and place it into the opening while the first portion of the ampoule works its magic on your skin. At the end of the day, take off your makeup and apply the serum right before moisturiser.