All military uniforms include a hat. When you are costuming a play, you should provide a hat with all costume uniforms in any outdoor scenes. A garrison hat is an army hat that is easy to make and requires very little fabric. It should be made of the same fabric as the uniform and trimmed with metallic midi braid (narrow trim). Gold buttons can be used for the military insignia. From a distance they look correct.
Cut two pieces of fabric 12 inches wide by 11 5/8 inches high. Cut two pieces of lining fabric 12 inches wide by 3 5/8 inches high. Round the corners of one of the 12-inch sides. Taking off 1/2 inch on each side. The rounded side will be the top of the hat. Round the corners on all the other fabric pieces in the same way.
Pin the fabric pieces together with the right-sides touching and all the edges even. Sew along the sides and the top of the hat with a 5/8-inch seam allowance. Trim the seams and clip the curves. Sew the lining pieces together in the same way, but leave a 3-inch opening in the top for turning.
Turn the lining right side out and insert it partway into the hat so that the bottom edges are even. Pin the bottom edges of the hat and lining together, matching the seams. Sew the edges together with a 5/8-inch seam allowance. Turn the hat right side out through the hole in the lining.
Push the lining all the way into the top of the hat. When the lining is fully inserted, the hat will be 7 inches high. There will be a 4-inch band of the hat fabric around the bottom edge of the hat, below the edge of the lining. Press flat the fold in the bottom edge of this band. Fold this band up 2 1/2 inches to form the brim of the hat. Press the fold at the bottom of the hat.
Sew the opening in the lining closed by hand. Sew midi braid around the top of the folded-up hat brim. Sew a metal shank button on the front left side of the hat, centering it between the top of the hat and the top edge of the brim.
The midi braid and button should be the same color. You can pull the lining fabric out and sew the opening closed by machine or just leave it open. It won't show. Midi braid is usually sold in packages.