This is a great tutorial if you don’t want to spending the money to buy a jacket from a cosplay site. It also makes a light jacket to wear if it is warmer weather. This is also a great jacket if you are larger sized. You can find these work shirts as large as a 5X.
First, start by purchasing a men’s khaki colored work shirt. The link goes to a shirt you can get at Walmart for $20 or less depending on sizing. You’ll want it in either khaki or desert sand color. Also make sure to buy thread in a matching color.