Throw a Slider
A slider (nickel curve) can be thought of as a combination of a fastball and a curveball. The ball is held off center and spins forward like a curve but with the fingers moving through the ball like a fastball. Allow your fingers to cut through the ball and let it come off the thumb side of your index finger. Do not twist your hand underneath the ball. For a right-handed pitcher a slider should break down and away from a right handed batter. Obviously the speed of a slider is between that of a curve and a fastball and its break is less than that of a true curveball.