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Mousse It Up
Mousse gives roots a boost and creates volume without stickiness. Avoid creams and heavy gels, which weigh hair down. (Spray gels can effectively add some height, when used in moderation.) Work the mousse into damp hair and comb through so all of the strands are coated. (We like John Frieda Luxurious Volume Thickening Mousse, $6.)