Session length and focus

I used to have this problem as well and found that after folding, trying to determine the hands of those who are still in is a good way to stay focused. I start with hand ranges and then eliminate possibilities based on VPIP, PFR, bet sizing/ strategy for each street, etc. After a while I can get pretty close and then when I do have a playable hand I can better determine what they have.

agree with fatguy, concentrate on your opponents take notes of what cards they are playing, if you have a HUD running see if the hands that they are showing down with correlate with their stats.if you still have time on your hands open another table but dont sit in , just watch and observe it as well, see if you can put a player typr to each player by watching them , then try and put them on a typical range for their position, modify the ranges for each street and see if the actual cards they showdown mean that your read of them was good or not .when you are coping doing that with the extra table then you can start playing that table .eventually you can start adding extra tables as you get more experienced and better at putting players on ranges.