The first—and hardest!—part of setting up Swagger is preparing the specification for your complete API. This is meant to be written in YAML Ain't Markup Language (YAML), and can be difficult to get right. However, you can use a web editor, which you can run at your own server (go to https://swagger.io/tools/swagger-editor/ for the necessary download) or online at https://editor.swagger.io. After writing that, however, setting everything up will be truly easy, needing just three lines of code!
YAML is a recursive acronym that stands for YAML Ain't Markup Language. If you want to learn more about it, visit http://yaml.org/.