How do you open up the chambers for the regis?

First, Dive down the deep area in Route 134. Then, in front of the Braille underwater, go back up. Then at the far wall with the Braille inside, Dig there. Then in the last room, have Relicanth first and Wailord last in your party (or the other way around, I always get them confused). Then after examining the Braille again, the tombs containing the Regis will unlock.

Get a Relicanth and put it in the 6th slot of your party, and get Wailord and put him first. Now go to the Sealed Chamber or whatever it's called(off of my favorite floating city) and make suer you have read the Braile. Do waht the instructions say, I'm pretty sure it says use Dig. Do that then that will open up and you complete the next task then the caves open.

I'm sure this question has been answered plenty of times already, but:
-Be sure to have at LEAST the first 7 Badges, as you will need Dive to get the Regis.
-Capture a Relicanth. They live in the seaweed underwater near Sootopolis city.
-Capture a Wailord. If you don't have one, catch a wailmer on routes 132-134 with a super rod. They should be around level 40, which is the level Wailmer evolves.
-Get the TM for "Dig" from The Fossil Maniac's Little brother in Fallarbor Town.
-Head west from Pacifidlog town.(it's location can be found on the PokeNAV's map)
-Keep to the lower middle of the area and you should reach a small area of water surrounded by a rock on 4 sides and whirlpools on 4 sides with a small patch of deep water that's 4 spaces big.
-Dive into the water (with 6 Pokemon including the Relicanth and wailord)
-Head south until you see a message chiseled into the rock. Stay directly facing the rock message and use dive. You'll be in the sealed chamber. Face the North wall's middle message and use dig, it should open the wall. Then put relicanth in the front of your party, and wailord in the back of the party. Head north with the proper lineup of Pokemon and the ground will shake. The 3 regi Ruins are now open.

The 3 ruins are:
Island Cave-RegiIce-SouthWest of the route between Petalburg City and Dewford.
Desert Ruins-RegiRock-In the Desert where the Go-Goggles are Required.
Ancient Tomb-RegiSteel-South of Fortree on the Route to Lilycove.

You go to pacifidog town and go all the way to the far left of the island then you use surf and go on the farthest current down then at around route 132 or 133 go to the lowest part of the current and you should hit a sandbar if you did this right...use dive then go to the far end when you get to the white scroll you need to resurface so that you go into the cavern...go to the far end and use dig then put relicanth in the front of your party and wailord in the sixth position go to the end then you go to the end when you have the Pokemon in the right position a tremor should happen and the doors will open


REGIROCK is in the desert read the inscription -> walk 2 paces to the right then 2 paces down and use strength

REGICE is on route 105 in the sandbars with trees enter the chamber read the inscription wait 2 minutes and then open the wall


REGISTEEL is on route 120 chamber fly into the first room

First catch a wailmer and evolve it to wairlord and catch a relicanth...then...go to the Pacifidlog town..go to the fast current's keep low...find the Dark Spot...dive there...get outside the cave and find the roock...read the sriptures and surf up...you will end up in th unederwater caver...go to the very end of the wall...read it and use dig...a hole will open ...go inside...read the the wall at the end...then put your wailord at first party and Relicanth at last. The screen will shake and it will say the Three doors have opened...

Go to the route with the currents dive down go up to the braile dive up bacl go to the end of the cave use cut go up to the new end put a relicanth in thetop of your party and a wailorn on the botton press a next to the brail now the rgi doors will be open.regice is in route near granite cave registeel is in the route next to lilicove city and regirock is in the dessert.