Painting animals is a challenge for many artists. One secret to getting a realistic texture is working with a three-color process. The first colour is your base. The second is a highlight colour mixed from the base with a small amount of white. The third colour is a shadow colour mixed from the base with a small amount of very dark brown. Once the shading is in place, it is a simple matter to add the hair texture to give your lion a lifelike coat.
Collect lion images from animal books and websites. Choose photos, rather than drawings or paintings for hair and colour details. Select the main colour for your lion's coat from these images. In the case of an African Lion, this will be a golden yellow. Purchase oil or acrylic paint in this colour, white and dark brown
Mix your highlight colour by blending equal parts of your base yellow with white. Mix the paint thoroughly so that the colour is consistent throughout the paint.
Create the shadow colour in the same way, but adding dark brown instead of white to the base colour. Mix it thoroughly for a consistent colour.
Apply the base colour over the entire area of the lion's body in a fairly heavy coat with a medium width art brush. Start the next step while this paint is still wet.
Load a smaller brush with the highlight colour. Paint highlights, anywhere that the lion's body would have a raised area, including the top of the muzzle and back, the top muscles and skeletal shapes that appear in the fur, and the side of these same shapes that is toward the sun, and therefore catching light. Blend the highlights along the edges to smooth them into the base colour.
Apply shadows in the same way, focusing on the opposite side of the same shapes you highlighted, the bottom and sides away from the sun. Blend the shadows into the base colour to keep the coat smooth at this point.
Dip the medium width brush in all three colours and paint the mane of the lion. Use wavy motions to add body to the coarser mane hair. Use your images as inspiration. Allow the colours to blend, adding more of any of them as needed to get the desired effect.
Use a fan art brush, or other coarse, wide-bristle art brush, to drag through the fur on the body of the lion, creating short, hairlike grain patterns. Follow the shapes you created in the lion's body, studying your images for inspiration. Add more highlight, or shadow, lightly as needed to create the hair effect.