How are Generic elements and camera angles used to create suspense in the attic scene of the Exorcist?

One element is the music, there is none. This is used to create suspense because you are looking for what she is.

Camera angle, it is filmed from behind her as if someone or thing is looking at her from behind objects and above to suggest she is weak.

The empty rat traps say it wasn't the rats.

The stereotypical vulnerable, isolated young women alone in the attic in her nightie.

The candle light flickering off of objects to make it harder to see.

When Carl came up into the attic the suspense dropped because brought light and more sound to the scene. 

It's in the middle of the night and dark.

The title The Exorcist suggests something will happen.