first,CHANGE YOUR ATTITUDE.
you should exchange the role you are playing in life with your son.now suppose you are the little boy who has always been making mistakes.say,what will you do when faced your daddy's shouting and cursing?anything but fear.would you like to betreated like that again and again?the answer,sure enough,is NO!for a child,attitude is more important than the content.what he remembers is not where his mistake is but your shouting.
second,CHANGE YOUR VIEW
ask yourself,why your little boy always make "mistakes"?are they really mistakes?if you can't find the answer,just ask your son in friendly tone,remember,to ask or discuss rather than question.then he will tell you what he thought before doing it,you should be on his side,think like a little boy,maybe you will find a totally different answer.you are given the duty to help and guide him but not order him.
the last but not the least,think twice before you speak it out,take a deep breath,tell yourselt that the boy is not your son,not your private possesion,but your closest friend.what will you do?what?family line?!just forget it!that is just an excuse!come close to your boy,hold his tender body in your arms,and speak to him in a soft voice:"are you tired?are you hungry,my dear?"