Grunge roots with highlighted ends is the look that has captured the A-list's imagination right now. Drew Barrymore leads the way with her look - perfectly blended - it's cool yet sophisticated. Other grown-up takes on the style include Rachel Bilson's dark roots through to caramel ends and Jessica Biel's subtly placed highlights; both are groomed to perfection. If undone styles are more your thing, look to Pixie Lott and Alexa Chung for inspiration. Their hair has a rock vibe thanks to the combination of dip-dying and dishevelled texture. To get Alexa Chung’s look, ask for vertical slices of colour that are two to three shades lighter than your own, on the under section of your hair. For Drew's style, your stylist should apply three different levels of lightener using a free-hand smudging technique.