Hyrule Castle
Go through the Castle Courtyard while avoiding ALL the guards along the way
until you reach Princess Zelda at the end of all that stuff. Talk to her and
listen to her story, then she'll give you a letter, which allows you to get
through guarded gates without a problem. As you leave, you'll run into Impa.
Talk to her and she'll teach you Zelda's Lullaby and escort you out of the
castle, away from the guards. Now, run through Hyrule Field until you reach
Lon Lon Ranch near the middle of the field.