Follow the PEN

Plain English Network

It's an FAA writing style guide.

https://www.google.com/url?sa=t&source=web&rct=j&url=https://cfapp.icao.int/fsix/_Library/Plain%2520language%2520guidance.pdf&ved=2ahUKEwjqy8Xkv_jpAhXlQzABHfZEA7sQFjACegQIARAB&usg=AOvVaw0mNaDnVSZiBWnVaGnn3MT1