Press windows button then type cmd and press enter.
Then cd to the FarSky folder and run:
java -Djava.library.path=native\windows -classpath "farsky.jar;lib\jogg-0.0.7.jar;lib\jorbis-0.0.15.jar;lib\lwjgl.jar;lib\lwjgl_util.jar;lib\slick-util.jar" game.Main
Should work on mac/linux too but you have to replace the native path and \ with /... To the creator: you can make a .jar that contains all assets and works on all platforms without problems in like 5 minutes also please add ARM?