Before leaving the vehicle, fully press the clutch pedal down, move the shift lever into R (Reverse), and firmly apply the parking brake. Once the shift lever has been placed in R (Reverse) with the clutch pedal pressed down, the ignition key can be turned to LOCK/OFF, then remove the key and release the clutch pedal.
See Manual Transmission Operation.
Chevrolet Cobalt Service & Repair Manual. Adjustments
Brake Pedal
1.
With ignition OFF and brakes cool,
apply brakes three or four times, or until brake pedal becomes firm,
in order to deplete brake booster power reserve.
2.
Adjust steering wheel angle to highest
tilt position ...