Atticus shows this in the smallest of ways, such as with the family's ornery old neighbor, Mrs. Dubose, who makes a habit of taunting Jem and Scout when they walk by her house. Just hold your head high and be a gentleman, Atticus advises Jem.
As light continues to move though the atmosphere, yellow wavelengths are scattered leaving orange wavelengths. Further scattering of orange wavelengths leaves red as the predominate color of sunlight. Therefore, near sunrise and sunset, a cloud's color is what sunlight color it receives after Rayleigh scattering.
The color of sky is affected by a physical process called scattering of light by small particles in atmosphere. For particles that are really small, like air molecules, much smaller than wavelength of light, the particles tend to scatter more blue light (Rayleigh scattering Rayleigh scattering).