there are two ways...you can back up to the ledge behind you and throw her from there when the wind is blowing toward the ledge.
OOORR
you can use the windwaker to make the wind blow [north i think ?] and...still stand on the ledge and throw her.
i found it easier when youre higher off the ground, its more likely that she lands in the cavern.

the way i did it was when u back up on that ledge

use comand mealody on girl and she will fly