Katie Holmes, perrier THE EXPERT Colorist Michael Murphy has tended to the manes of Katie Holmes, Celine Dion and Ivana Trump. One of his most challenging color changes came a few years ago when he had to change Holmes's hair from a red hue to her original brunette in 24 hours. "She was a trooper and we pulled it off perfectly," he says. EXPERT TIP Swimmers should try to wash hair immediately after getting out of the pool to rinse chlorine out. If you can't get a shower, try Perrier: "The carbonated water will help wash away the chlorine and other chemicals," says N.Y.C.-based Murphy.