There is really no guide to sussing out what an oppenant has (poker would be far to easy otherwise and you would only win when you have better cards than the other players)
Firstly my advice would be to stop doing this and start putting people on a range of hands and this will come naturally over time so just play alot more hands.
So for example when villain raises say from MP to 3x you will assign them arrange (if you do not know this player well and have no stats you have little to go on)
But as the hand progresses you can start eliminating hands from the original range you assigned them, you do this based on the way they are betting in reaction to the cards that have come off. Again you just need lots and lots of hands before you notice you are right quite alot of the time.
If your not playing too many tables also watch what hands get shown down even when your not in the hand and make notes on these payers, which will make it easier when you are in a hand against them.
TD