1. you go to the gryphon master and jump on top of the right gryphon (while facing the gryphon master)
2. Jump onto the ledge against the wall to the right. This may take a few attempts.
3. Follow the ledge until you get to the end, then jump into the little crack in the hill.
4. Jump up the hill while in the crack and you know you are doing it right if you stop while jumping (kind of like an invisible ledge, and face the wall slightly while you jump up)
5. Jump on top of the wall and jump down into the white stuff and Tadaa! you are underneath SW.
Extra: There is a way from underneath SW to get behind the portal in SW but i'll let you find that out