I disagree with this anon. Positivity and "good" does not equal to a balanced and healthy chakra. Doing charity and being compassionate has bollocks to do with clearing chakras. Rather, a chakra is at its best when it is free of blockages and you can use it to its full extent. In the case of the throat chakra, you should feel no restraint regarding your communicating with others and expressing of emotions and feelings.
Violence and negativity are also necessary, for sometimes only through them does change for the better come. Bottling up emotions does not bring well being, it needs to vent out. Indulging yourself in excess positivity will bring stagnation, and make yourself passive to others, which, I can say through experience, is a massive hinder to any whatever purpose you have. That being said, too much of negative will have an ill impact on your well being, and will have you on edge, burnt out and sick, so strive for balance.
That being said, here's an exercise that should help you unblock it or help the energy flow:
Affirm to yourself something in the lines of "I express myself. I am free of blockages. My throat chakra is clean." and chant "Haum", focusing on vibrating your throat chakra region as much as possible. Imagine the chakra glowing a sky blue color, becoming stronger with every chant. After repeating the chants about 7 times, focus on the chakra, and breathe in golden energy to it, with the intent of balancing it.
I won't lie, this could take a while to work, specially if you've never done anything like it before. Log every meditation in a notebook, and don't think too much about it through the day.
Additionally, seek out active and physical ways to express yourself. Meditation brings forth change, but you can speed it up. Play an instrument, chat with people, sing a little, write down your feelings, etc. When faced with a situation where you'd usually shy away from, face it. Don't get into trouble though, have common sense.