Using Aureolin, Rose Madder Genuine, and Cobalt Blue will yield a soft black while using Winsor Yellow, Permanent Alizarin Crimson, and Winsor Blue will yield a bold black. If you have a basic paint set, whatever red, blue and yellow you have will work. Magenta and cyan are common red and blue to use.
Use slightly more of one or two of the colors to give a different look to the black. If you use a paintbrush to dab paint onto the palette, be sure to use a different brush for each color so that you don’t mix the paints except on the palette. You will most likely not be able to create the same black from one time to the next, so be sure to make enough to paint what you want to.
If you use a paintbrush to mix the paint, swirl the brush gently and don’t press down too hard. You can ruin brushes by pushing them too hard against the palette.
If you have time and paint to spare, experiment with the color. Add a little brown or green to the black to paint pine trees at night, or add some yellow for the sun reflecting off of black metal. Mixing paint by hand usually won’t give you an exact black, but your black will have more character than a pure black.