Painting portraits is a great hobby that gives both the artist and the model much pleasure. It is better for both however if the texture, color and flow of the hair closely matches the model. Follow these steps to obtain more realistic colors in your next portrait.
Before painting hair, you should always have the rest of the face finished first. The flesh color extend into the hairline. This is so that the flesh color shows through and the hair does not look unnatural. Remember that hair is much more than one layer, therefore, you need to paint it in layers. There are also hundreds of shades of hair color. To keep it as simple as possible try to base each portrait with, blonde, brown (this includes red), black or gray.
Under paint the entire hair area with a very light mixture of one of these colors. These are called undertones. This under painting will actually be the highlights because as you work you will not cover all of this. Notice where the dark or shadowed areas are and paint them in. Now use a darker color and start stroking in hair strands. Black is the opposite. Start with the darkest as the undertones, then add lighter layers. Continue until you are satisfied with the results. It is very easy to overdo hair. Know when to stop!
Here are the colors you will use for any hair tone. Remember to apply the undertones first
Blonde (Reds) Titanium White, Cadmium Yellow Medium, (Alizarin Crimson)
Use Burnt Umber to darken blonde and red hair
Brown Titanium White, Burnt Umber
Use Cadmium Red or Ivory Black for red or blackish tones
Black Ivory Black Undertones
Warm Black - Ivory Black & touch of Brown
Cool Black - Ivory Black & touch of Blue
Gray Titanium White, Ivory Black for a Gray Undertone
Warm Gray - Ivory Black & touch of Brown
Cool Gray - Ivory Black & touch of Blue
Start the first layer, or undertones with a very watery mixture of paint. Use a medium to large brush because you are not painting details. Don't try to paint in individual hair strands at this stage. Start addinf more paint color to your brush and add some more layers. Pull the brush in the direction of the flow of hair. Use a liner brush to add some indications of individual strands. Add any deep pockets of color to really give the portrait depth. I added some deep shadow on the side of the neck.