Some I will write as versionmc is the version of minecraft on which the plugin was tested
Install JDE 16
Install spigot-versionmc.jar
Run spigot-versionmc.jar
Go and chane in the eula.txt file eula = true
Run again spigot-versionmc.jar
Then, after the server is fully started, transfer ddl.jar to the plugins folder and write "rl" in the console