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With Coco's help, Katy Perry goes from alabaster to California Gurls.
PREP "Blotchiness is obvious on light skin, so exfoliation is key," Coco says. "Work your whole body with exfoliating gloves and avoid moisturizing." (DHA, the chemical that changes your skin's pigment, adheres best to dry, clean skin.)
AND PREP SOME MORE... To avoid looking like an Oompa Loompa, always start with a skin test. Try tanning liquids by dabbing them on a concealed zone, like your inner bicep. "Then pick the formula that looks the most natural," says Coco.
SELECT YOUR FORMULA "Pale skin goes orange the quickest, so avoid products with orange or yellow number four," advises Coco. "And opt for a DHA concentration of five to seven percent. Anything higher is too intense."