Examine photographs and Civil War history books of period uniforms. Recognize the distinctions between Union and Confederate regalia. Union soldiers, for example, wore blue uniforms while the Confederates wore gray.
Collect as many old blue and gray wool coats, pants and black and brown shoes as possible. Distress the fabric of each item to make it look war-torn. Cut the elbows or knees of coats and pants, for example. Fray the trimmed fibers with 120-grit sandpaper and a wire brush. Rub the paper and brush along the entire surface of each uniform to add authenticity.
Cut brown vinyl straps to various lengths. Loop and bond the ends of each strap together with white glue to create Civil War shoulder straps and belts. Cut and bond ovals from paper plates to act as straps and belt buckles. Bond one buckle to each strap.
Paint the buckles gold or silver. Bond metal buttons to the wool coats. Fleck each uniform with brown or green paint to emulate dirt and stains from rough war conditions. Allow each costume piece two hours to dry before handling or wearing.