Texas Holdem Tournament Strategy - Poker Tournament Fundamentals by Rick Braddy
... That's because calculating and playing the pot odds isn't yet second nature to them. If that's you, then you definitely need to get the poker odds ingrained into your subconscious mind, so they’re second nature and you don't even need to think about them while you’re playing. Find yourself a good Texas Holdem poker odds calculator, practice with it, and you’ll learn the odds of drawing each type of hand and find that you don’t need to think about them.