How do I manuever in the sewers

Hint 1 of 6:

Use the map that came with the game.

Hint 2 of 6:

See the goggles on the wall ? WEAR GOGGLES.

Hint 3 of 6:

EXAMINE GOGGLES and set the dial to the proper Activation code.

Hint 4 of 6:

For example,  SET DIAL TO 111.

Hint 5 of 6:

The goggles show you the present coordinates ( see map ).

Hint 6 of 6:

At Valves, push the shape that corresponds to the tunnel you want.