If you want to lighten a gallon of dark colored paint, what should you do?

To lighten a gallon of dark colored paint effectively, the best approach is to add white paint. Adding white paint directly introduces a lighter pigment that can diminish the darkness of the original color, allowing you to achieve the desired shade without altering the overall color quality. This method offers control over the lightening process, enabling you to gradually achieve the preferred hue.

While options such as mixing a lighter color may seem viable, they might introduce unexpected hues that do not achieve the intended lightening effect. Mixing with water can dilute the paint but may not consistently lighten the color or could alter its finish and coverage. Starting with a new can of white and adding dark would not be effective since it reverses the lightening intention. Therefore, adding white paint stands out as the most straightforward and reliable method for lightening dark paint.