This doesn’t mean you have to dye your platinum-blond locks the darkest brown, but it might mean asking your colorist to make a light summery hue more intense, darker, shinier—or all three. Let these celebs be your inspiration: Each one is brilliant at taking her signature shade lighter or richer as the mood (or season) strikes.

Taylor Swift

To add richness and shine to light hair and help counteract summer sun damage, your colorist may apply a golden-toned glaze, brush on some lowlights (the opposite of highlights—a deeper secondary color) or do both.

Cynthia Nixon

To change strawberry blond into a dramatic, saturated red, your colorist may apply a layer of demi-permanent color in a lighter shade and then add a second layer in the desired hue—“a bit like priming a wall, so the final color ends up true,” Carey says.

Eva Mendes

Rich, chocolaty and shiny make for a gorgeous fall brown—a color that’s hard to hold on to in summer when the sun turns deep-brunette hair brassy. Your colorist may apply two layers of demi-permanent dye for a deep and lasting result.

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