Having a dominance of warm or cool can help you create a mood for your painting and may help you express the feeling you had when you first saw it. Blues and greens can create a calm feeling, dark cool colors a somber mood, lively colors in reds and yellow are colors that can make you happy when you look at them.
You can see the warm and cool colors on the color wheel: the side with the red and warm yellow is warm, and the other side with the blues and greens is cool.
Each primary color will also be categorized as warm or cool. It is helpful to make a chart in your sketchbook, divided in half, of all the colors, having one side for warm and the other side for cool. When you add a new color to your palette, add a sample of this color to your list. Usually, a color that has a little red added to it will be warm, and a color with blue or green in it is cool. As an example, Ultramarine blue has a little red added to the formula, while Thalo Blue has a little green added.
CRL- Cadmium Red Light AC- Alizarin Crimson
CYM- Cadmium Yellow Medium CYL- Cadmium Yellow Light
A warm sunset painting made with a limited palette.
Try tints of all your paints in your sketchbook for a great reference tool.