What is the correct visualization of "first left down the hallway"?

Question

I hear a lot of native speakers say something like this:

• Once in the arena take first left down the hallway
• Take your first left down the hallway.
• When you come to the second floor, make a left and then take your first left down the hallway.

I am confused by such sentences because I am not sure if, when speakers say "first left down the hallway", they mean this:

or that:

In other words, do they mean "take a left into the hallway and go down"(first picture) or "take left out of the hallway"(second picture)?

Answer 1

Once in the arena, take the first left down the hallway would usually be taken to mean

Once you are inside the arena, go down the hallway and then take first left.

but

Once in the arena, take the first left, down the hallway would be taken to mean

Once in the arena, go straight ahead until you come to the first left, which leads down the hallway. Go down the hallway.

Answer 2

I think your example would require some punctuation or context to clarify the situation. You may not have the benefit of punctuation if the instructions are oral.

• You're in a large room with two exits at opposite ends. One is a door leading outside; the other is a hallway. In this context, the first left is off the hallway.
• You're in a large room with several doors and a hallway (no doors) leading off it. In this context, the first left is probably off the hallway.
• You've entered a room with exits along the left side, a door at the far end, and windows looking outside to the right. In this context, the first left is off the room and leads to a hallway.
• You've entered a corridor with exits along both sides and a door at the far end. In this context, the first left is off the corridor and leads to a hallway.