You might want to get some wallet upgrades from Beedle's Airshop before opening any goddess cube chests that you unlocked.
You should also drop off your Iron Shield at the Item Check in the Bazaar and get a wooden shield for the next area. There will be electric enemies and the Iron Shield won't protect you from their electricity.
It would also be a good idea to get more bomb bags from the Bazaar.
Go into the chamber under the Goddess Statue and put the Amber Tablet in place. Then fly to the yellow light and dive down to reach Lanayru Mine.
You end up on a tower in Lanayru Mine. Down below, you will see a robot that is just like the one that you might have seen in the scrap shop of the Bazaar.
You will hear a buzzing sound. This is a Sand Cicada. It's on the back of the tower. You can catch it with the bug net.
There is also a goddess cube here.
Up ahead, you will find a mine cart that you have to push out of the way. Push it all the way off of the ledge and push it to the end of the track so you can run up the other side of the ledge and get to the top.
After going up, go to the left and you will find a blue crystal in the middle of the area. Hit it with the sword to activate it. The area around you will be covered in grass, and the robots will come to life. Fi explains that the crystal is a Timeshift Crystal that creates a temporal distortion field, putting the surrounding area into the past.
Look for the Ancient Flower near the wall in this area. It's a collectible item.
There is a mine cart already in this area. Get into it to ride it to a room that has a chest that contains 20 rupees. Then ride the cart back outside.
There is a mine cart that, if you didn't push it earlier, is just outside of the time field. Push it into the field to make it float. Then get in and it will go through the other door.
The mine cart will stop just before the edge of the time field. Throw a bomb into the basket that the statue is holding to make the statue fall down into the gap. Go through the passage.
There is quicksand, also known as sinksand, up ahead. You can run across it for a short distance, but it very quickly uses up your stamina, so you can't run very far at all. Throw bombs into the statues to create platforms to stand on. One of the statues hides a passage that leads to a chest containing 20 rupees. You can also find Lanayru Ants if you break the pots. You can catch these with the bug net.
Up ahead, carefully make your way across the room, avoiding the electricity-spitting monsters. Be sure to run straight for the platform to avoid running out of stamina. If you run out of stamina while running through quicksand, you will sink down below and lose a heart.
At the end of the room, there is a mine cart. Push it to the end of its track and then run up to the next area.
Bomb the rocks on the mine cart track up ahead, then roll a bomb at the rocks in the narrow sand passage. Roll some more bombs to reveal and then activate the timeshift crystal at the end of the passage. The quicksand will become grass and a Deku Baba will appear on the ceiling. Kill it and go across. Keep in mind that if you hit the timeshift crystal again, it will deactivate, and you will have to hit it again to reactivate it.
Up ahead you can catch a Gerudo Dragonfly with the bug net.
Follow the path to reach the chest that you saw earlier in the big quicksand room but couldn't reach. It contains a Goddess Plume.
Drop down onto the grass and go to the mine cart at the side of the room. If it isn't in the time field, push it into the time field. If you didn't bomb the rocks covering the track up ahead, do that. Then get into the mine cart to go through the door.
You will reach Lanayru Desert. Fi will warn you of sinksand, which you can see on the map.
Bomb the piles of rock near the mine cart to find another timeshift crystal. Activate it. The time field will extend slightly farther ahead, revealing some vines on the wall that you can climb.
Go up the vines and walk along the ramp all the way to the bottom, where you can go through an arch to reach a chest that contains a blue bird feather.
There is a red creature in a shell down below. It is called an Ampilus. Use a shield bash with a wooden shield to knock the Ampilus away, then hit it with the sword. If you do not have a wooden shield, use the bird statue to return to Skyloft and get one. When you fly back to the yellow light to go back to Lanayru, you can choose which bird statue to go down to, allowing you to return to this area right away.
Run up the slopes on the broken walls nearby to find some Sand Cicadas on a tree, and a chest that contains a tumbleweed. If you see an actual tumbleweed roll past as you walk through this area, you can catch it with the bug net.
Up ahead, you will find some cages. Throw a bomb into the cage with the hole on top to reveal a timeshift crystal. Use another bomb to activate it.
Some bokoblins will appear. They hold electric weapons and are called technoblins. If you go close to the robot here, it will call out for help. The easy way to get rid of the technoblins is to lure them to the edge of the time field and throw a bomb behind them. They should run past the edge of the time field and turn into skeletons. If not, you will have to kill them with the sword. They can be difficult because if you hit their weapons, you will get zapped and lose health. Try using shield bashes or the slingshot to stun them.
Once the Technoblins are gone, the bars of the cages will go down. Talk to the robot, who will notice your beetle, saying that it's an older Lanayru model. He will upgrade the beetle, adding pincers that can pick things up and also drop things while flying.
On the left, there is a bomb on the tree. If you make the hook beetle fly into the bomb, it will pick it up. You can press the Z button to look down while flying, then press A to drop the bomb. Do this to kill the monster in the sand and drop bombs into the baskets on the statues on the wall.
Use the statues to reach the gaps in the wall, some of which contain rupees and treasure. Then go to the area beyond the sinksand here.
The birds up ahead will fly around and drop boulders on you. You can use the hook beetle to drop a bomb on them and kill them.
There are ampiluses in the sand up ahead. You have to use the hook beetle to drop bombs on them. Then you can run onto their shells to catch your breath after running in the sand. Then run to the area with the green stamina fruit. There is a goddess cube on the side.
Save at the bird statue and go up the ramp. Push the mine cart off of the edge to give yourself a shortcut.
The sand up ahead is flowing like water. When you kill the ampiluses, the shells will move with the current. Make your way across to reach a small cave entrance.
You will find yourself in the desert gorge near the Temple of Time. Use the hook beetle to activate the nearby time crystal.
Kill the technoblin or scare it out of the time field by throwing a bomb at it, then catch the dragonflies with the bug net and pick up the ancient flower. Then get into the mine cart and go to the other side.
Use the hook beetle to catch a bomb from this side and drop it into the empty tree trunk to the left. Then use the beetle again to take a bomb into the area under the trunk and bomb the Deku Baba. Then get into the mine cart and get your slingshot ready. Shoot the pink switch on the left side before the mine cart bumps into the bars.
After going through the area under the tree trunk, you can go talk to the Goron standing by the rocks. The path to the Temple of Time is blocked.
Go to the right. There are some tall rock spires here. Some of them have rocks on top. Use your hook beetle to bomb the farthest pile of rocks, revealing a timeshift crystal just above the mine cart. Activate the crystal and kill the bokoblins, or use a bomb to make them run out of the time field.
Talk to the robot in this area and it will say that the Temple of Time and the mining facility are connected underground. The robot will update your map, turning it into a map of the area as it was in the past.
Get into the cart to ride it past where the robot was. Then look in the wall to see a timeshift crystal there. Activate it with the beetle, causing the rail to go up to the goddess cube. To send the goddess cube to the sky, you will have to do a skyward strike while riding in the cart.
After going past the goddess cube, go through the cave entrance up ahead.
Run across the quicksand area and Fi will talk about your map. The robot's map will show you areas of submerged stone that are safe to walk on in the sinksand. You can place beacons to mark the safe paths that you can run across.
In this area, you will find an Amber Relic. You can run up the slope to reach the upper level. Save the game at the bird statue.
Hit the nearby timeshift stone. Get rid of the technoblins and then talk to the robot, who will explain that the machine here is the generator that opens the way to the mining facility. To activate the generator, you must first turn three dials that are hidden around the desert. Fi will appear and add the dials as dowsing targets.
You can find an ancient flower in the grassy area below.
Find the Electricity Dial
One of the dials is in a cave to the north. Use dowsing to find a crack in the north wall. Bomb it open and go inside.
You can't use dowsing in this area.
Bomb the pile of rocks in the center of this area to reveal a timeshift crystal. Activate it and the entire area will go into the past.
There are two small chests on the lower level. One contains a red rupee and the other contains a blue rupee.
The Ampiluses have turned into Ampilus Eggs. They generate electricity occasionally. The hook beetle can pick them up and fly around with them.
On the far wall, there is a device that Fi says can be activated with a source of electricity. Stand on the switch to open the small gap on the back side, then roll an ampilus egg into the slot to open the bars on the wall, being careful not to hold onto it for too long to avoid getting shocked.
Beyond the bars, you will find a dial. To turn it, use a forward thrust attack to put your sword into the slot. Then turn the Wii Remote to rotate the sword to the left until the dial clicks. Then press A to push the dial in, turning it on. A lightning bolt symbol will appear on the top.
Find the Water Dial
Dowsing will show you that there is another dial on the west side of the big circle in the sand. There is a crack in the tall rock wall on the west side of the circle. Bomb it to reveal a timeshift crystal. Then throw a bomb into the statues' baskets to make them fall.
Activate the time crystal and then turn the dial like you did the other one. Do a forward thrust attack to put your sword into the slot, rotate the Wii Remote to turn the dial to the left, then press A to push the dial in and activate it. A water drop symbol will appear at the top.
Go Toward the Third Dial
The third dial is southeast from the generator. Use the submerged pathways by looking at your map to see where they are. You can walk over to that side of the circle on a path that is surrounded by Electro Spumes and some boulder-dropping birds.
Get a Piece of Heart
Before continuing along to the dial to the southeast, there is a crack in the wall northeast of the giant circle in the sand. You can reach it by walking along a submerged path that you can see in the map. Bomb the crack, then kill the yellow chuchus along this path. Near the blue chest at the end, there is a large yellow chuchu. After getting rid of the chuchus, open the chest to receive a piece of heart. Go back the way you came, running to the left at the end to reach the solid ground.
Find the Fire Dial
There is a dial southwest from the generator. As described above, you can reach it by walking along one of the submerged paths shown on the map. You will know that you are on the right path if there are some Electro Spumes around the path and boulder-dropping birds.
Up ahead, you will find a building that the dowsing signal is pointing to. There are some ampiluses in the area and some sand cicadas on the walls of the building.
Look for the bars on the wall up ahead to the right. Run up the wall where there is a red bar. You will automatically grab the red bar and pull it down if you run up the wall there. This opens up the bars, giving you a shortcut to the first area of the desert.
Save at the bird statue and go inside of the building.
As before, there is a timeshift crystal in the center of the area under some rocks. Bomb the rocks and activate the crystal. Go around killing the technoblins. There are two small chests on the lower level that both contain five rupees.
To get to the far side, though, you need to deactivate the time crystal. Kill the nearby ampilus and run onto its shell. You can ride the shell to the far side of the room on the flowing sand.
Once you reach the far side of the room, climb up the box that leads to the ledge of boxes along the side of the room. At the far end of this ledge, open the blue chest to get some Eldin Ore, then use the Beetle to activate the timeshift stone. After that, push the orange box down to the lower level. That gives you a shortcut to the far side of the room.
Jump down to the area near the timeshift crystal and use the beetle to pick up an ampilus egg. Fly it over to the other side, then use the orange box that you pushed down to this level to go up to the ledge on the side of the room, and run to the far wall where you dropped the ampilus egg. Step on the button on the device in the wall, then roll the ampilus egg into the slot that opens, again being careful not to hold it too long to avoid getting shocked.
Go through to the dial and activate it as before. Do a forward thrust with the sword, then rotate the Wii Remote to turn the dial to the left, then press A to push it in. A fire symbol will appear on the top.
Activate the Generator
Go back to the generator. It's where the robot is who told you about the three dials. Activate the timeshift crystal if it isn't active. To activate the generator, you need to turn each of the three dials and push them in at the proper places on the dial.
How do you know where to turn the dials to? Look at your map. The big circle of sand corresponds to the generator itself. The spokes of the circle in the map correspond to the spots on the generator that you can turn the dials to.
The electricity dial is to the north, the water dial is to the west, and the fire dial is to the southeast. The first dial that you push will be the water one, so turn the dial so that the water symbol is pointing west on the dial. The next one is the fire symbol, so turn that to the southwest on the dial. Finally, turn the electricity symbol to the north on the dial.
If you do it correctly, a structure will appear in the center of the circle. Save at the bird statue. You can climb up to the top of the structure if you want, but there is nothing interesting there right now.
Go inside to Lanayru Mining Facility.