Hi Please start by using a soap free face wash. This will help to stop your skin from drying out. Also make sure to use an anti pollon containing sunscreen at least three times a day. This not only prevents tan but also protects your skin from the pollution. at bed time use a good moisturizer. Eat healthy avoid junk foods and exercise regularly. Vegetables and fruits which are brightly coloured contain lycopene and carotenoid which help the skin fight the sun.