Giac83 Ganon is invisible, but if you try to attack him where you think he is then he might appear. Keep attacking him to make him appear. Once his color is brown shoot him with the silver arrow. The silver arrow will finish him off, and you will get the triforce of power. Once you have the triforce of power the door where Zelda is will open up. Once you walk to Zelda the game is over.

Watch the finishing off Ganon video below.

http://www.youtube.com/watch?v=Jfi944XiCNg