Part 4: Dragon Roost Island
Acquiring the Wind's Requiem
Take the tunnel through the middle of the island. Swim across to the small land mass containing a tombstone with some markings on it. Check the stone on the left and you will see symbols. Pull out the Wind Waker and play the song that is on the stone. You will learn the Wind's Requiem.
Getting to the Rito Tribe
After the cutscene head back near the King of Red Lions. You will find the trail leading up the mountain is blocked by giant boulders. Simply use the Bomb Flowers to blow up the boulders and travel up the mountain. Near the top you will notice the path drops out - just Sidle across to reach the other side. Now drop down and use the Bomb Flower to blow up the rock holding the blocks.
They will fall down - now enter the area behind the red Postbox. Once the cutscene with the Postman ends follow the path and go inside the entrance. The Chieftain will ask you to help out the tribe by curing Valoo - the dragon - of the illness that irks him. Once you are done talking to the Chieftain you will receive the Delivery Bag from the Postman.
Speaking with Prince Komali
Head up the path spiraling upwards and go inside the first room. Talk with the little girl - Medli - and you will get the Father's Letter that you will need to give to Komali. Jump down to the bottom floor and enter the only room that does not leave the area - the one between the red crates. Follow the short hallway and enter the door to find Prince Komali. Equip the Father's Letter and show it to him.
Now exit Komali's room and exit through the passage to the left - the one with the Rito standing by it - to find Medli standing at the bottom of the area next to a giant boulder. Talk with Medli and agree to help her. Now pick up Medli and stand on top of the small rock formation. You need to throw her to the top of the edge when the wind is blowing towards it. After doing so Medli will give you an Empty Bottle.
Entering Dragon Roost Cavern
Equip the Empty Bottle and scoop up some of the water near the giant rock. Now climb up the broken bridge opposite of where you threw Medli. Look around to find a Bomb Flower. Use the water to nourish the bomb flower back to health. Pick up the bomb flower and toss it over the ledge to blow up the giant rock – causing water to fill up the area.
Jump into the water and swim across to the other side. Now pick up the bomb flowers and throw them into the pots that the bird statues are holding. Jump across the statues that should now have fallen to enter Dragon Roost Cavern.