I designed and made a trilby hat. I decided to make a version of a trilby hat from the 1950s era. Before making the trilby hat I watched instructional videos. I learned how to make a brim and a sideband using cardboard. Another video instructed me how to trace a pattern including seam allowance. and how to cut it out onto fabric. Once I cut the fabric, I put the hat together following  instructions from other videos.