Chevrolet 2007 Colorado Owner's Manual page 134

To release the parking brake, hold the regular
brake pedal down. Pull the bottom edge of
the lever, located above the parking brake pedal,
with the parking brake symbol, directly rearward
to release the parking brake.
134
If the ignition is on when the parking brake is
released, the brake system warning light will
go off.
Notice: Driving with the parking brake on
can overheat the brake system and cause
premature wear or damage to brake system
parts. Verify that the parking brake is fully
released and the brake warning light is
off before driving.
If you are towing a trailer and are parking on
any hill, see Towing a Trailer on page 306.