Those things I mentioned are straight from Mike Caro’s Book of Tells and are very accurate to this day – I use them routinely.
Take a rainbow flop K 4 8 for example, and your opponent checks his cards before choosing a course of action. Generally (and this is without any specific situation or player information) that means he knows he paired the King, but the other card was not important enough to remember, but it could have been a 4, and he would like to see if he made Kings up. Same tell is often used for suited flops, in which when your opponent looks at his holdings you can be near certain he has one of the suits that flopped but not two – he would have remembered he had 2 clubs and not have needed to look.
Your opponents who are unaware of these tells often exhibit very basic ones. If they are bluffing
they tend to tighten up and not move a muscle in their body, why; because they are acting. Contrasted to the opponent whose foot and whole leg is rhythmically tapping beneath the table waiting for your call; this is not an act but rather a release of tension, and you should probably not call or raise without the nuts.
Pay attention to yourself; I’ll bet you’d be surprised what you could learn.
Anyway, these are just examples of standard tells, but it’s the why behind these actions that is the true question; unfortunately it is often overlooked despite really being the most important. Caro goes to great lengths to emphasize this point. Yet whenever I bring this up with my poker playing friends they can always tell me that he’s bluffing because he doesn’t move, but don’t really understand the why behind the information they are interpreting, and then complain to me when the guy flips over quads.
In the example I mention, it’s near meaningless to a poker hand, but may give you a better clue to you opponents nature. That and I’m genuinely curios since I see this one so often – it must mean something; is it “dammit no callers, whew – got away with one there, or something somewhere in the middle?