1.While up against a wall and peeking around a corner, press x to
draw your pistol to shoot around corners.

2.When crouching, run as fast as you ca and
press B to do a commando roll (it is a good idea to commando roll
passed small spots of light with guards around to remain
undetected).

3.while your pistol is drawn, press up, down or
left trigger to use the laser on it (helpful for shooting guards
in the back of the head) if you try to use it while two guards are
talking the other guard will see it and attack you.

4.use the optic cable at all doors to make sure
that u wont be detected.