There are a few things about punishing the kid:
1) Never punish the kid because and while you are angry. Calm down, access the situation, then assign punishment
2) No physical harm...To be, paddling the behind is fine, slapping the palm is fine, choking/hands around neck, close fisted punches, etc are not.
3) Be consistent in punishment.
4) Most of time, be private about the punishment. Save the public dress down for special cases.
5) Make sure your kid knows you love him...no matter what happens...and yes, even when you are punishing him.