I usually only watch the big pot hands at a table. As I am watching I try to guess exactly what each player holds. The more you do this the better you will get. I only watch the big hands because those are the ones that will have the biggest effect on me. These are the hands where you get to see which players are ready to felt their draws or overpairs. You get to see how they use their bets to get the money in when THEY want to get the money in, and its all free.