ENHANCE YOUR SHINE Since long layers don't require frequent cutting, splurge on products that can impart serious sheen to your hair and keep it looking its best. La Prairie's Cellular Intensive Hair Mask, which is composed of Cellular Hair Repair Cream and Cellular Hair Nourishing Oil ($275 for both, plus the comb), visibly restructures the hair shaft, renewing silkiness and restoring body. Once a week, apply the oil to your scalp and comb through to your ends. Next, smooth on the cream, working from ends to roots. Leave on for 15 to 20 minutes, then rinse.