Part 1: Outset Island
The Journey Begins...
Travel across to the opposite side of the island and enter the house with the Red Postbox out front. Climb up the ladder to the second floor. After the cutscene with Link's Grandma finishes go back to the platform to find Link's sister. Aryll will give you the Telescope. Equip the Telescope and zoom in towards the Red Postbox to see the Postman. Aryll will tell you to look up and you will see a girl fall from the clutches of a big bird into the forest. Now you get to go save the girl but first you need a sword.
Saving the Girl from the Forest
Travel to the house beside Link's Grandma's - the one with the guy standing outside the second floor - and he will ask you to target him. After doing so you need to enter the house. Speak with Orca to acquire some sword training. Once you finish all the technique Orca has to show you will acquire the Hero's Sword. Now take the trail up the small mountain behind the house near the platform you start the game on. You will need to use the sword to cut the small trees down to progress further.
Once at the top you need to go across the bridge and enter the cave. Travel towards the center of the area you are in now and you will have to fight an enemy. Once you take him out - climb onto the small tree stump and jump across. Continue by climbing up the newly accessible tree stump and jump down. Two birds will drop off some more enemies for you to fight. After beating them the girl - stuck in the tree - will awaken and fall out of the tree.
Setting Sail with Tetra and the Pirates
After the cutscene that ensues you need to go talk to Link's Grandma. Now climb up the ladder to the second floor where the shield was located. It will be missing so jump back down. Link's Grandma will give you the Hero's Shield. Now go back and talk to Tetra - the girl you saved - and get ready to set sail with the Pirates towards the Forsaken Fortress.
Once aboard the ship you need to enter the door and go downstairs to talk with Niko. Niko tells you how to jump across platforms using ropes. Once you make it to Niko you will get the Pirates treasure - a Spoils Bag. Now head back up and Tetra will ask you to climb up the ladder to reach her. Upon doing so Link will get launched into the Forsaken Fortress.
Continue to Part 2: Forsaken Fortress