color for a quilt

When I am deciding what color should be in any quilt, I use the color wheel.  There are three parts to the color wheel. They are primary colors, secondary colors and tertiary colors.
A color wheel is an abstract illustrative organization of color around a circle that shows relationships between primary colors, secondary colors, and tertiary colors.
As an illustrative model, I use red, yellow, and blue primaries arranged at three equally spaced points around their color wheel. Secondary colors represent color mixtures resulting in  green, orange, and violet.  They are placed between their maker colors. The Tertiary colors are a mixture of one primary and one secondary color. There are six.  They are red orange,  yellow orange, yellow green, blue green, red violet, and blue violet. They are placed between their maker colors. As you see that all colors are made from blue, yellow, and red then you can see that you can find colors that have one of those colors in it and it will blend, such as red matched with red violet.  That is just the basics.  Then if you take those colors and mix varying amounts of either white or black you get tones.  Add white and you get tints and add black and you get shades. 

This is just the tip of the ice burg as there is adjacent colors,complimentary colors monochromatic colors.  Color also has temperature.  Warm colors and color colors.  Colors also have movement.  A group of colors go back into space and a group of colors go forward into space creating the illusion of depth.

One can spend a life time studying color.  But the average quilt can take the color wheel concept and improve their color blending ability by 100%.  Happy quilting.