So, the labyrinth achievement is a bit difficult since there are no hints across the internet which rules or paths to follow to do the dream labyrinth in "the guest" correctly on your first run.
The game will automatically autosave right before the labyrinth, you only have to walk through the brightly-lit hotel door to enter it.
Then there is a short or long path to the first "room", which I will call now the battery room, and there are always two doors to choose between
a) the battery room and the book shelves room
b) the book shelves room and the projector room
c) the projector room and the TV room
d) the TV room and the final "We are science"-door where you only have to walk on to end the labyrinth.

Now, you could walk across the labyrinth and remember the correct doors. If you chose the wrong one, you will end up in the battery room to try it again and choose the other door until you finally walk through the correct combination.
BUT, since you want to do it on first run, the labyrinth will reset the correct combination everytime you load the game, so you need my hints.

There are some details in the game that you may think may help you, but they do not help, trust me:

Neither the birds or the music give away any hints,
nor the leaves on the floor,
nor the design of the doors (which are exactly similar),
nor the position of the sun (which is mostly to the left or right of you),
nor the time that you stay in one room,
nor the direction in which the path behind the door bends,
nor the lenght of any path leading to the rooms,
nor the last turn that you did before entering the room.

The solution is a bit difficult:
If you don't want To walk through the labyRinth randomly, pay exact attentiOn to the path leading to any room (to the battery room as weLl) and
- count how many times you waLk right and how many tImes you walk left aNd
- remember your first turn.

If you turn riGht more times than left, choose the right door next.
If you turn left more times than right, choose the left door.
If you turn exactly the same amount left as right, choose the door according to your first turn
(for example, you enter the labyrinth through the hotel door, then walk left, right, left, right to come to the battery room, you will next choose the left door [because 2 times left, 2 times right, but first turn was left]).

Good luck with my guide, I hope it saves you the time that I have wasted. :)