The kinds of hands that players choose to play at any given time vary as widely as we do. So in order to ensure that you have the best possible read on a player comes down to concentrating on all hands played.
Some players will never play bad hands, from any position.Some will widen their hand ranges when they have position while others will only ever play good hands such as pairs or an ace with a high kicker. And because it is hard to remember how every player has played every hand the importance of making notes on players is essential.
If you are quite a regular player and keep notes you will find that over time you will start to build up notes on many of the players you will come across day to day as many players stick to playing certain stakes and types of games. These notes can often be invaluable especially when faced with big decision early in a game before you have had a chance to really see how they play. If you have already have notes on someone it will make the decision so much easier. If for example you have marked a player as tight then you know you have to have a good hand to take them on. Or if you know that someone is a perennial bluffer you know that your middling hand may well be good in this situation.
However, even after keeping detailed notes you will still find that often you will be playing with people you have never played with before so you need to establish the kind of hands that in general people enter pot with. These hands are usually pairs and big connected cards (10 upwards). This will help you recognise “safer” flops to either bluff at from position or make continuation bets at. Fops that are low or have pairs on are often the safest kind of flops to bet at as in general people won’t be in hands with lower cards and if there is a pair on the board it means there are only 2 , instead of 3 cards, that players can have connected with. But it is also important to remember that players in position will call with a wider range of hands than those that have acted earlier in the hand so when trying to evaluate your opponents hand keep their position in mind when trying to work out what they may be holding.
A good way to try and improve your general read is when you are not in hand, watch the action carefully and try and put each player involved on a particular hand and if it reaches showdown, see how close you are. You will find that by doing this every time you play, your read will start to improve as you get used to spotting betting patterns and your predictions of what they have will become more and more accurate. I say to do this when you are not in hand, especially when you are a beginner, as you will be able to take a much more objective view. When people first start playing poker, it is often harder to evaluate things objectively as nerves and adrenaline can cloud your judgement somewhat and the pressure of the situation can make it harder to second guess what your opponent may be holding. Also, by concentrating in hands you are not in you will see a much wider variety of situations than you personally will find yourself in.