When you're out of position, you need to represent the flop hard if you choose to represent it. That means if the pot is 12xBB, then bet 12 or more BB. Anything less sends mixed signals and erases your reads. In other words it opens up a wide array of hands that will make a move on you. QT, Q9, Draws, Bluffs.

Repping a flop correctly allows you the luxury of pairing down possibilities. Rep it correctly and an opponent with QT will hesitate before acting. Rep it improperly and they become more aggressive, effectively representing a better hand than they actually have, and forcing you to put them on it. Remember what your opponent thinks you have. It's important. Sometimes you need to tell them what you have so they throw out the possibility of having some kind of fold equity on you.

A good rule of thumb I use... if my goal is to take down the pot now, I expose my strength immediately, and with complete disregard for concealment. I'm not looking for more chips from my opponent at this point. I want them scared, and I want them out.

Other than that if you rep that flop correctly and get raised anyway, then just fold it without emotion. I'll always allow someone to make one or two moves on me before I decide to fight back, especially in cash game. Most people at mid levels don't even have moves unless they're a maniac. Maniacs pay you off eventually anyway. So why lose chips to a better hand that is probably just letting you know it's time to fold? If it's not a better hand, then chances are it's a player you'll be busting soon enough.

Not respecting raises is a newbie mistake. You have to learn to respect all raises, before gaining the right kind of reads to fight back against the few premium players who make gorgeous moves on you.