Using labels and notes of players

I want to start using these tools but I am not sure of how to do it properly. Does anyone take notes of other players or use colours to remember how they play?

a HUD is much better for that, but it costs money. If you don't have a HUD, then it is useful to take notes, in case you see the opponent's cards, to see how he played. But the thing about notes is that they are valid only during that session, not in another. For example, you are playing a tournament and you take notes on players. The mext day you play cash and you find a player who has a note from the yestarday, they are not reliable, at least it is what I think

I think everyone has different colours for different types of players.example green for Lag ,red for solid player ,yellow for tag ,blue for grinders or multi tablers etc.Notes on these vaious types of players are helpful if you have seen them play certain cards in a certain way .Notes are useful I think more if you have seen the player make the same type of play repeatedly over a large sample size............scorp