Let’s take a look at how using a double split complementary palette can help simplify color choices to ensure a cohesive, colorful painting without being overwhelmed by too many hues. First decide on the light source's temperature and its complementary shadow color. Choose two colors for light and two for shadow. Then block in local colors and shadows, ensuring color harmony throughout. Use blending modes and soft edges to integrate colors smoothly, and refine details like ambient occlusion and highlights.