Preparation
Preparing a military figure is a crucial step in the process that shouldn't be rushed. Most figures are cast with two-part molds, which leaves a flash or mold line around the figure. Occasionally that line is visible, and sometimes small pieces of metal or plastic stick out. These can be trimmed with a sharp X-acto knife or similar tool. Also, before painting apply a primer to the figure. Most miniature paints are acrylics, and primer helps the acrylic stick.
Environment
Military figures are usually small, which makes painting fine details and shading difficult. Paint in bright light and use a directional desk light that is pointed directly at the figure. Painting is easier with the figure on a hard, flat surface. Holding the figure in one hand while painting with the other makes fine detail hard to manage unless . Jewelers' magnifying glasses, which clamp on a table and have a movable neck, are excellent for helping to see the details and insignia needed for a proper military uniform.
Tools
Assemble an array of different tools. For the first coat of paint, the base coat, use a larger brush or a sponge to apply the paint. For fine details, use a paintbrush with only one or two hairs. A selection of brushes in different sizes will make life much easier when you are painting.
Colors
Gather an assortment of colors. Uniforms from different militaries have different color schemes, and adding in flesh tones, personal touches and other pieces like horses and vehicles will require nearly every color imaginable. Get extra black and white paint, because shading is essential. All of the colors used on the figure will need to be shades in places.
Patience and Practice
Learning to paint a military figure accurately takes a lot of practice. Many collectors have hundreds of figures and spend hours each week painting them. Expect the first few figures to come out less than perfect, and don't get bothered when it comes time to do them over. Gaining the skill needed to paint fine details on small figures takes patience, but it can be a rewarding experience.