Primary colors can't be created, they must be provided to you. But once you have the primary colors -- red, blue or yellow -- all you have to do is mix colors together to create more colors. Create secondary colors by mixing two primary colors. Create tertiary colors by mixing a primary color with a secondary color. Whether using oil, water color, markers or crayons, create new colors with a simple mix.
Mix red and yellow to create orange. Orange is a secondary color.
Mix yellow and blue to create green. Green is a secondary color.
Mix blue and red to make purple. Purple is a secondary color.
Mix yellow and green to create yellow-green or chartreuse. Chartreuse is a tertiary color.
Mix blue and green to create blue-green, aquamarine or turquoise. Aquamarine or turquoise are tertiary colors.
Mix blue and purple to create blue-purple or violet. Violet is a tertiary color.
Mix red and purple together to create red-purple or magenta. Magenta is a tertiary color.
Mix red and orange together to create red-orange or vermilion. Vermilion is a tertiary color.
Mix yellow and orange to together to create yellow-orange or marigold. Marigold is a tertiary color.
Mix red and green to create brown. You can add white or black to the brown to make it darker or lighter.
Mix white with a color to create a tint. For example, mix white with red to create pink.
Mix black with a color to create a shade. For example, mix black with red to create burgundy.
To create a less intense color, mix in a some of its complement -- the color opposite it on the color wheel. Red's compliment is green. Blue's compliment is orange. Yellow's compliment is purple. Create a dull and muddy rust orange color by mixing in a little bit of blue, for example.