Grip it in a backhanded fashion with your first two fingers cupping the butt. The edge should face away from your body, the flat running along the inside of your wrist and point aiming at your elbow. Never let the point cross in front of your body. it should always be off to your side or behind when walking. Not only is this an extremely effective method of concealing a knife when about to shank someone in the prison yard, it grants you excellent tip control, ensuring the knife isn't a danger to you or people who bump into you.