This part will get you through the entire Sand Temple.
Inside the Temple
There's nothing we need to get outside the temple, except pots for breaking if we need to get hearts, so let's proceed inside.
In the first room that we enter, go to your right until you come across a hallway of rolling boulders. Weave your way past them as you proceed northward to a passageway on your left. Stop at the place where you see three blue-grey tiles and time an arrow shot past some rolling boulders into an eye switch. The door to your left will open. Go through there into a room where you see a small chest that contains a single rupee. However, after you open it, the door will close, and some Stalfoses will rise up and attack you. Fell them with your arrows quickly, as more will pop up from the ground. After the last Stalfos is defeated, the closed door will reopen, and another small chest will appear in the room which contains a small key. Take it with you back to the first room you were in and use it to open the locked door to the north. Go through the door and up the staircase to Floor 2.
Go across the spiky bridge, then drop down a level and go south. Avoid the sand creatures called Gerunes in the next room and head east from there and then north into a room where you must maneuver around some rolling spikes to reach the staircase at the north to take you to Floor 3.
Go south from the staircase into a closed-door battle with some Stalfos Warriors, using either arrows or bombs to take them down. The door in the lower left corner will now open. Go through there and head up the stairs to the treasure chest which contains our next useful item -- the Sand Wand. This item will raise up sand blocks for Link to use for various purposes which we'll discover. To use it, hold down the button for using the item and simply draw on the screen where you want blocks to be raised. It can also be used for freezing up Gerunes. As soon as we take the wand, Zelda hears a rumbling in the Temple and fears the worst.
Now let's go back to the room where we fought the Stalfos Warriors. You'll notice that in the closed-door battle, the door that was closed behind us didn't reopen. So how do we get out and back to the staircase? Stand near the platform at the upper left corner of the room and raise Link up on a sand block to reach it. Then go to the right and head back down the staircase to Floor 2.
As we head back into the room with the rolling spikes, you'll notice that they'll start rolling uniformly together instead of separately. Use the Sand Wand to lift up blocks to stop one of the spikes temporarily so we can get an opening to run to the door at the south. As we reenter the room with the Gerunes, the door will close behind us before they attack. Freeze each of them with the Sand Wand, then strike them repeatedly with the sword. The closed door will now reopen, and two more doors to the north of us will also open. Go through either of the north doors and stop when you see the spiky bridge become a rolling spike that moves back and forth. Carefully raise up Link on a sand block so he can reach the platform on the north, then use more sand blocks to freeze up the rolling spike so he can use it as a bridge again to reach the staircase going back down to Floor 1.
Head back to the hallway where the rolling boulders are and you'll notice that they're now rolling in a new pattern that will make going up that hallway nearly impossible. Go to the sand patch on your right and raise Link up on a sand block to get him up on a platform, then go as far north on that platform as possible and wait to make a timed run into the same passageway on your left. Back where the three blue-grey tiles are, use the Sand Wand to move the two boulders out of your way with sand blocks so you can get a clear shot of the eye switch with your arrow, reopening the door to your left. In the room on your left you'll see little dust clouds kicking up. These clouds are created by creatures called Ergtoroks, which will surface to spit spiky balls at you. As they are forming their clouds, use the Sand Wand to raise them up on sand blocks to stun them. Make sure Link is also raised up with them so he can quickly slay them with the sword. A small chest will now appear on a higher platform to your left. Raise Link up to that platform to open the chest, which will contain a red rupee worth 20 rupees. Now have Link raise up as many sand blocks as possible on the sand patch to the south. This will uncover a small key Link can take with him. To go back into the first room, raise Link up on enough sand blocks near the south for him to jump down from.
In the first room you'll notice that there's a boulder on a patch of sand, and at the south is a catapult that's near a switch orb. Use the Sand Wand to maneuver the boulder with sand blocks so that it's resting on the catapult. Then strike the switch orb to launch the boulder so that it breaks a wall and reveals a staircase. Take the staircase down to Basement 1.
Go to the left and create a sand bridge for Link to cross over a patch of quicksand, then open the locked door and head into the room where there's two Gerunes and two floor buttons that need to be pressed down to open a door to your right. Freeze them with the Sand Wand, then pick them up and place them on the floor buttons. Quickly get through the door before the Gerunes unfreeze and cause the door to close back up. Now along a winding path of quicksand going to the right, create a sand bridge for Link to go across, making sure you also watch out for arrow launchers. Then go up the stairs to the right where you see a big block with a blue diamond-shaped gemstone on the side which you need to move onto a diamond-shaped blue lock in the center of a sand patch. To roll the block onto the lock, move it in the following directions from its starting point: south, east, south, east, north, west. This will open a door at the lower right. Go through that door and you'll see a stream of rolling boulders to your left in the next room, plus a catapult with a switch orb to your right and a floor button to the south. The floor button will cause a bridge to appear crossing a gap to the south, but it needs to be held down or else the bridge will retract. With Link standing on the button, maneuver a rolling boulder with the Sand Wand onto the catapult, then use an arrow or the Boomerang to strike the switch orb. This will break open a door that's across the bridge to the south. Now maneuver another rolling boulder over onto the floor button to keep it pressed down so Link can cross the bridge.
Now head over into the room on your left where you see two blocks with a red gemstone on one side and a blue gemstone on another. We need to move these so that the gemstones fit into the colored locks. The red gemstones will open a door to the north of us past a patch of quicksand where the Big Key Door is behind, while the blue gemstones will open a door to the lower left of the room. Press the floor button on the left to open another door on the left that will take you back to the staircase to Floor 1.
Go through the lower left door and head west, avoiding the rolling spike in the passageway, until you reach a room with two Stalfos Warriors in it. Slay them and then head north, using the Sand Wand to raise up Link and to stop the lower rolling spike so that he can go onto the platform and press the floor button, causing a door north of him to open. Go across the spikes through the door, and you will get into a closed-door battle with some Ergtoroks. Stun them as they're forming dust clouds with the Sand Wand, then raise yourself up to slay them. The closed door will reopen, and another door to the north will open. Go through that door into a room where there's nothing but a patch of sand. Raise up all the sand in the room until you see the Big Key pop up. (You'll also raise up a green rupee worth 100 rupees.) Take the Big Key with you back into the room with the blocks and raise up a sand bridge to cross the quicksand to the Big Key Door that you can now open. Go down the staircase to Basement 2.
There's nothing that you really need to get on this floor, just pots for breaking to get hearts and a blue portal to take you back to the entrance of the Temple. Proceed to the door at the north to meet the Temple Boss.
Temple Boss: Skeldritch
As Link enters the chamber, he sees a giant skull with a horned helmet and a spinal column come to life. This is Skeldritch, the Sand Temple boss, whose main form of attack is to launch boulders at you. He will also spew forth an energy beam from his mouth and chase you around with it.
There are four catapults located around the outer periphery of the chamber that we can use to launch boulders back at Skeldritch to knock off parts of his spinal column. Use the Sand Wand to capture one of the rolling boulders and maneuver it onto one of the catapults to launch it at a spinal segment. The first two segments will be easy to knock out, but the remaining three are armored, so we need to hit them from behind. Distract the skullhead so that he turns away from the catapult, then use an arrow to strike the switch orb to launch the boulder at him. When he gets down to the last spinal segment, he'll start launching boulders at a faster rate, and you'll need to raise up a lot of sand blocks to keep a boulder from being crushed by another one.
Once all Skeldritch's spinal segments are blasted away, the jewel on his head will be exposed. Trap him by using sand blocks and raise Link high enough so he can strike at the jewel with his sword. Eventually Skeldritch will decay and turn to dust, which means that you have defeated him.
A staircase will appear, and so will a treasure chest that contains your next Heart Container. Go down the staircase into the chamber where a treasure chest will contain the Bow of Light, which lets you fire Light Arrows by keeping the stylus on your target until it is charged up. Up ahead across a chasm will appear a blue portal. Fire a Light Arrow at the golden eye switch that's near the blue portal to create a bridge for you to cross. Now step into the blue portal to return to the entrance.