Improving post-flop play

[theblitz]

A recuring theme in many posts is that you need to improve post-flop skills in order to move from a break-even/slightly winning player to a good play.

Pre-flop play is (generally) easier as there are many lists and lots of advice what to play.

The question is: How do I improve my post-flop play.
"Just practice" is not a real answer.

What should I be looking for?
What books should I be reading (or re-reading)?

I'm sure I am not the only one with this problem. It is the main thing that stops me moving up to higher levels.