buy a calibration tool like the pantone huey or xrite colormunki. You are dealing with a TN LCD so you are never going to get the contrast or color accuracy that you could get with an ACD or iPad (Which use IPS LCD).
I would stay away from the Huey Pantone personally. I have heard lots of bad reviews and pink casts to MBP displays after those calibrate them. Stick with a Spyder 3 or Spyder 3 Pro. Those come highly recommended.