I am also trying to learn a cutter. I asked a team mate of mine and this is how he explained it.
Gripping the ball like a 2-seam bring your fingers together so that they are more on the inside of the seams rather than ontop. Putting more pressure on the middle finger. Don't snap your wrist but rather throw it like you would a football almost. I know that may sound confusing but almost just get on the side of the ball.
For me sometimes I can get a nice tail to the ball and other times it does noting, yet I haven't really practiced the pitch that often. Good Luck!