A little help please

[EMcWilliams]

I've been playing poker seriously for about a year now, and I feel as if I need some help on my game, and was hoping this would be the place to find it. I consider myself to be a Tight player preflop, and I raise and re-raise when i deem necessary to add the aggresive portion to my game, or so I feel. Is being aggressive preflop really just raising or is there something im missing? Additionally, I don't feel as if i'm too aggressive post flop, and I could really use some suggestions as far as what to do post-flop aggressivness. Finally, I know many of the key concepts of play i.e. Pots odds, tells, semi-bluffing and most of that fun stuff,but yet when im playing i cannot seem to apply it. Any suggestions...

Thank You