Get Fire Arrows early
First, get the scarecrow song as a kid. To do this, go to Lake Hylia as a kid through Zora's Domain. Talk to the scarecrow on the shore, the fist by the lake. Take out your ocarina and he'll want to play. Play a song you made and that's your song. Be sure to remember it. Next, you'll need the Longshot. To get this, beat Dark Link in the Water Temple. As an adult, go to the scarecrows and play the song for the first one. Piere will now appear where there is a green Navi but nothing there. Now, when the sun is rising, shoot the sun with an arrow by the Water warp point (with the Water Medalion on it. When the Fire arrows appear, go down the hill. Don't drop, just go to the edge. Play the scarecrow song to make Piere appear. Use the Longshot to hook on and grab the arrows. Good Job! P.S. The Fire Arrows light things on fire. Duh!