There are many customization options in the game and the control scheme can be changed to your preferences.
Windowed or fullscreen.
WASD for movement.
Mouse to look around. If you walk forwward while moving the mouse left or right you change walking direction accordingly.
Middle mouse button and mousewheel is not necessarily required but useful.
Optional mouse speed and smoothing.
Enable Viacam headmouse movements are recognized.
Several volume settings for speech, effects, overall and music.
Spoken text has subtitles if it's important. Things that are not in the main line of the story like stuff you overhear while walking around are not subtitled.
Noises are not close captioned, but sounds that have a important role are made visible, e. g. if someone discovers you.
VAC speech recognition works.
Narrow subtitles with not quite dark edges. Adjustable of sorts.
Health and Mana in red and blue.
Edges that you can climb up are made visible in red.
Objects you can interact with have a yellow glow when the mose is over them.
Crosshair is a black dot but can be changed in the options.
Weypoints throughout the world are white.
Texts are rather small and they have a parrow font-face. Thexts are quite lengthy.
In-game tutorial.
Optional aim assist and auto aim with adjustable accuracy.