One of the poker tips I read several months ago has to do with the flop. You've got AK, you've made your bet, it's been called, and here comes the flop. What is the first thing you're looking for? (Hint: It's not an ace or a king.)
You should be looking at the person who called you, to see if the flop helped or hurt them. You should be looking for their reaction. You can look at the flop itself in a few seconds. That first instant the cards come down though, you should be looking at another player. Same with the turn and the river.
I've tried to do this, but get distracted and maybe only really do it about a third of the time. On Friday, I've got AK, and the flop comes with three little cards. It's checked to me, and I bet. I get one caller.
The turn is a king. I'm looking at the cards, not the player, and he checks. I bet. He thinks for a minute, then says "I think you've got it. When that king came down, you smiled." He folds.
I need to watch other players more. And smile more.