With a sturdy incline setup give yourself a wide stance with your legs. Place one arm in front of you supporting your weight on the ring. The pushing arm will operate exactly as it does in a normal pushup. Shoulders should be active and supporting the push arm. Elbow travels back and to the side without flaring out at any point in the movement. Lower yourself until full range of motion until the ring is by your ribcage. Press out hard with absolutely no twisting of the torso.
Keeping control of the ring is difficult but absolutely vital, proceed with caution when starting out.