While filling your brows, one should always make sure not to use the product in heavy quantity, this will unnaturally darken your eyebrows and they will end up looking fake.

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WRONG

The key to make your eyebrows look natural is to always fill in with a light hand on the spaces that has less hair and needs to be filled, do not fill in where it is not required just to make your hair darker. This will lose the natural effect.