I suggest to lock yourself in a room, because you may feel foolish, I know I do, lol. But if I'm not sure how my charactor's should act, according to the situation, I stand in front of a mirror and literally make faces of how I picture the char reacting. Sometimes I will bunch fists and shake them at my reflection, jump up and down, move from side to side; everything.
This way when I write, I don't "over do" the situation, which I have a tendency to do,
Hope I didn't confuse anyone, hehe. And I hope this might help someone out if their not sure how a char should react. Have fun!

