I'm sure there are numerous videos available on the internet site for the Golf Channel. Do you start to read the green while still walking up to it? Water has to run off so you can look for collection and exit points, and water won't drain into a bunker.
Feel the green with your feet as you walk around the hole. Once you get used to it you can feel the uphill and downhill slopes.
And also like the above post imagine pouring water on the green and visualize which way it would run.
One more tip from Faldo. On the practice green take a hole or two and read it from below or behind your ball, Put a coin or tee in the ground where you want to start your putt. Then read it from above or behind the hole and see if you get a different read, If you do put a different coin or colored tee in the ground where you want to start your putt.
You will find out if you read better from behind the hole or behind your ball or the same. Good luck.