When in combat, rather than telling the players that their characters took X amount of damage, I will communicate the severity and placement of the hit (e.g. "The goblin's blade slashes your arm; the cut is deep, but not life-threatening"). As 3.6 uses "bloodied" status (at half hit points, characters take a -2 penalty to everything), I will let them know when their wounds have brought them to that state and, if necessary, when they have been rendered unconscious.
I will also roll for perception skills rather than tell the players to "roll a spot check," watch them roll low, and then say "nevermind." This is especially helpful when characters are searching for traps or treasure. So often they see the low roll and decide to try again, even though their characters should be convinced that there is nothing there.
We will see how it goes.