After washing your face, turn the shower on hot, close the door, and let your skin soak up the mist. Once it feels dewy, apply a product with hyaluronic acid, an ingredient that pulls moisture from the air into your skin. "It works better in humidity," says Dr. Noëlle Sherber. Then, sleep with a small humidifier by your bed to keep air at the optimum 30 percent humidity level.
SPT Travel Size Personal Humidifier, $49; amazon.com.