Is there a way that you can ensure being difficult to predict at Poker? For example, if you never bluff, people will eventually get to known that and it will reduce your ability to profit from good cards? Anyone there knows techniques or trick to avoid being easy to read?
Practice makes perfect that's the only way to do that, but even if a player is good at hiding his expression and his feelings, experienced poker players are also good at reading your body language, so it's not only your facial expression but also your body language that you need to hide for you be competitive in poker games.
Casino Royale!

Yeah, but you are right still the over smart poker champion will use such a category to bluff you so it's too much complicated if you take lot of things into account while predicting the oppositions cards.
So play your game at best while use bluff occasionally.