How do I set up sensitivity and gyroscope aiming?

Everything is on the Sensitivity tab, and all of it is available during a match too.

Camera sensitivity — set separately for each aiming mode: General Sensitivity · Iron & Handmade Sights · Holosight · Optical Scope

While shooting — When Firing from the Hip.

Gyroscope

• Gyroscope Mode — Off / While ADS / Always. "While ADS" turns the gyro on only while you're aiming.

• Gyroscope Sensitivity, plus separate sensitivity for Iron & Handmade Sights, Holosight and Optical Scope

• Invert Vertical · Invert Horizontal

Additional — Acceleration and Camera Smoothing.

Note: the gyroscope sensitivity slider was adjusted in a recent update, so if you had it tuned, the same number may feel different now. Worth re-checking your value.