When applying an oxidative color for a darker result, color is applied from:

When applying an oxidative color to achieve a darker result, it is essential to apply the color from the base to the ends. This technique ensures that the new color is adequately deposited at the roots, where the hair is typically the most resistant to color absorption.

The base of the hair, being closer to the scalp, tends to process differently compared to the rest of the hair due to natural heat from the scalp, which can help enhance color development. By applying color at the roots first, you allow for a more uniform finish as the ends, which have been previously colored or are more porous, will process slightly faster compared to the roots. After applying to the roots, it's important to ensure that the color is blended through the rest of the hair for even saturation. This method helps ensure that the darker shade is evenly distributed throughout, resulting in a consistent and rich color outcome.