You should by all means try to collect as much as possible about your opponent. This can then be used when you take your decision, and hopefully you know more about the people you play against than they know about you, and may thus gain.
Would you ask someone who does not play poker how to read female poker players were guaranteed to answer something that has to tell to do? They might talk about a player’s roving eyes or shaky hands. Sure, there is a lot of information of how female poker players are physically acting at the table, but it is not the most important. There is also tell that you can only notice if you play poker live.
What style of play poker helps with your opponent?
What you should primarily focus on is not how opponents act, but what they actually do. Say you only study a player’s eye, but completely misses that he has raised ten hands in a row before the flop. It would be much worse than if the case was the reverse.
The key to reading the opponent is to establish their basic style of play poker. Playing the aggressive or passive, tight or loose? What hands do they play before the flop, and of these, which they play after a raise? How to handle the move? Do the semi-bluff often, or are they the type who would rather check-call if they are offered the correct pot odds?