I would like to know how to get the big key in the Deepwood Shrine because..

Backtrack to the large loose barrel and go inside. Suck up the spider web and fall through the hole. Use the Gust Jar to bring the lily pad over to you, and navigate through the water by using the Gust Jar in the opposite direction of the way that you'd like to go in. When you reach the pot puzzle, just lift and throw all of the lower pots except the lowest one on the right. Push it onto the switch and navigate over the downed bars. Push the lily pad in the direction towards the treasure chest and open it to reveal a Small Key. Grab the Compass by moving the right block up and the left block left. Go upstairs and use the Gust Jar on the slow patches to reveal a chest containing 20 Mysterious Shells. In the next room, use the Gust Jar to clear all of the slow patches to reveal 3 switches, which unlock two chests (10 Mysterious Shells x2) and a Warp to reach the Piece Of Heart. Go south and suck up more slow patches to reveal a switch, which unlocks a chest containing 10 Mysterious Shells. Backtrack to the beginning of the stage to find the Warp pad and collect the Piece Of Heart. Backtrack to the basement level with the lily pad and take it out of two rooms and to the northwest to find a locked door. Go through it. You must use the Gust Jar to navigate through the room by pulling the mushrooms with it and grabbing onto them to be slung throughout the room. Open the chest to receive the Big Key. Now backtrack to the very beginning and open the western doorway by sucking up the spider web. Collect the 20 Rupees in the chest and go unlock the other side. Use the Gust Jar to leap across the pool of water and reach the boss door.