Playing poker is quite simple if you are not pretending to smth elevated, but to become professional, not only skills matter but also personal characteristics, and this is very hard to teach
I think everything is based on your techniques that you use when you are playing to receive your opponents so they will not be able to understand your present mood. Professional poker players have different strategies they can put in place to confuse there opponents not to be able to read there mind. Experience also matters a lot so we have to know that experience is the best teacher.