Place the paint color you want to lighten on your palette. Acrylic paint dries fast, so only put out what you will use. If you plan to mix a large quantity, mix your colors in something sealable such as a jar.
Add a lighter color like titanium white or yellow to lighten, a little bit at time. Mix thoroughly with either a paint brush or a palette knife.
Add more of the lighter color until you achieve the light color desired. If the color becomes too light, add more of the original color to darken.
Create a value bar by adding the original color to the palette and spreading it across the palette. Take the tip of your paint brush and draw a line to section off the color into five squares. Add one part of a lighter color, such as white or yellow, to the second section to lighten, and repeat in the other squares by increasing the lightness by a consistent value, such as by two or four. Once completed, a value bar gives a reference for how to lighten colors.
Use one part Payne's gray to sixteen parts cadmium yellow pale to create a light green.
Add one part Payne's gray to sixteen parts cadmium yellow pale to create a light green.
Mix one part turquoise blue, four parts cadmium yellow and four parts titanium white to create bright light green.
Add one part cadmium yellow to sixteen parts of titanium white to create a light yellow. Add sixty-four parts titanium white for very pale yellow.
Mix one part cadmium yellow to sixteen parts of titanium white to create a light yellow. Add sixty-four parts titanium white for very pale yellow.
Use one part cobalt violet and four parts of titanium white to create a light violet.
Use three parts cobalt violet, sixteen parts of titanium white and one part of cadmium yellow deep to create light grayish brown.
Use three parts of cadmium red, thirty-two parts of titanium white and one part of phthalocyanine green to create a very light gray.