Well, as I do not know too much about your game, I would suggest investing in LeakBuster (http://www.holdemmanager.com/buy/4/leak-buster-no-limit
) - a software, which automatically - with the help of your HUD analyzes your game and detects leaks. This is quite essential, if you want to improve. The software is ingenious, and a great place to start.
Other than that, you would need to post plenty of hands in plenty of spots for people here to be able to help you. Or tell us more about your game - the stakes you play, the volume you put in, your goals, your poker history, etc.