Have the Night Vision Goggles unlocked and equipped. In the Exam Room of Alchemilla Hospital is an X-ray screen with writing on it: "Sarah 19". Examine the X-Ray while wearing the Night Vision Goggles. You will see an image of the Goggles on the screen. The image changes location, and seemingly its shape, if you alter your position in front of the X-ray before examining it.
The flashlight is useful for monsters detecting from afar, but it will make you noticeable. If you keep it turned off, you will be able to avoid monsters much easier. You can also sneak-attack them, even from a very close distance.
Enter this for the following costume.
In order to unlock extra options under the "Options" menu, simply beat the game once.
Run/Walk: Makes Travis Run by default.
More Blood: Makes the creatures spray more blood when attacked.
Noise Filter: Allows ability to turn off screen "Grain" effect making the graphics sharper.
Bloody Footprints: Travis will leave a footprint of blood with every step he takes.
Flashlight Filter: Change the light of the flashlight to a smiley face, soccer ball, jack-o-lantern or the mark of Samuel.
Conserve your melee weapons and use your fists. Technically your fists are your fastest weapon (and the strength of them never goes down).