HoW we correct our childrens bad habbits ......

Try to be strict with them ,change in your policies of handling them be polite while talking but impose restrictions whatever is possible in your hands.Tend to give moral guidence .If they don't obey ask someone else to solve the issue as sometimes children think we are talking shop for them,that way if outsider gives the moral teaching may be they follow the lesson and give up their vices.Also buy books on relative subjects to bad habits they have,in which all side and post effects of overindulging are mention,keep such books in front of your child.He may tend to read that, get some positive lecture and give up his bad habits.