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Jessica Isaac/Demand Media

Color grabbing or staining, one of the most common problems brunettes face when coloring their hair, occurs when the base tonal quality of the color is unevenly absorbed by overly porous or damaged sections of hair. If the base tone is cool or ashy, the hair turns green on the ends. Proper color selection will prevent the problem, but most do not recognize the problem until it is too late. Slapping on another color without careful consideration rarely fixes the problem and may cause it to worsen. To correct green-colored hair, you must counteract the green with the exact opposite color base: red.

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Jessica Isaac/Demand Media

Select a red-based hair color that matches the darkness level of your hair perfectly. If your hair is medium brown, select a medium chestnut color. Keep in mind that you do not have to select a red hair color, just a hair color with a red base. Many popular colors that appear plain brown have red bases including chestnut and warm brown.

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Jessica Isaac/Demand Media

Mix equal parts color and developer in the color bowl. Blend the two products together using the color brush until a creamy gel forms and the color is even throughout. Put on latex gloves.

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Jessica Isaac/Demand Media

Section the hair into 1/2-inch by 2-inch sections while applying color. Apply color only to the green-colored portions in each section using the color brush. Apply color, section by section, until all green portions are thoroughly saturated.

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Jessica Isaac/Demand Media

Set the timer for 15 minutes.

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Jessica Isaac/Demand Media

Apply color to the rest of the hair not affected by the green stain. Set timer for 10 minutes. Remove the gloves.

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Jessica Isaac/Demand Media

Rinse the hair with warm water until the water runs clear. Shampoo twice to remove remaining color. Condition the hair and towel dry. Allow the hair to dry completely before checking the color.