think of hold 'em as a guessing game, always try to put your competition on two cards, some are impossible to read as they will play anything, or dont understand the game or what they are doing, but for the most part the bets people place are for a reason and logically deducing that reason is key to reading the game.
example. your opponent raises 3 times the blind and you call with a pair of 7s
the flop comes k52
your opponent checks to you.
1. he has a hand like aq or aj and has missed the board.
2. he has a pair like yours and is afraid of the king
3 your opponent has hit a set and is trapping
4 your opponent was trying to steal preflop and has no hand at all.
well there is only 2 courses of action here.
1. check and gain no further information on the hand
2. bet and judge from his response where you are.
you place a bet half the size of the pot.
your opponent checkraises all in.
1. your opponent believes you to be weak and is making a play
2. your opponent has a monster and has trapped you
most likely in this scenario is #2 you can postulate they have either ak,kk,55,22, or aa
you fold and your opponent shows a set of kings
why you bet? by not betting there, you risk hitting your set and going broke from an unfoldable hand.
REMEMBER:ALWAYS PAY ATTENTION ALWAYS GATHER INFORMATION