How do you become adult link on Zelda ocarina of time?

go to kakariko village and go to the graveyard on the far left side(near the wall)open the grave closer to the entrance and jump in you will see damp'e talk to him and follow him you will get the hookshot go to kokiri forest and into the lost woods find your way through until you are at the stone plate thing sheik will tell you the song and then use your hookshot on the tree to get up to the platform