How to teach good habits and manners to a bad kid

I questions the term "bad kid." Children are 100% a product of their environment. They pick up everything like a sponge and spit it back out. Most are not "bad" but starving for attention and know acting out as the only way to get the attention they are so desperately craving.

If it is your own child, then I would say you need to take a REALLY long hard look in the mirror. There are new studies out now showing that you cannot tell a child what to do and have them retain it as a personality trait. They mimic whatever they see. So in other words if there is a specific behavior that has become a personality trait, they saw it repetitively somewhere.

If it is someone else's, then there really is no way you can "teach" them good habits. You are not with them enough, nor should you take it upon yourself to take over the role of their parents (no matter how much you may want to, unless it is a neglect situation then you need to contact the proper authorities in your area). You can however establish a way you will accept them to behave in your presence.

You can quietly tell the child "Not around me" and they understand. The children as I said are not "bad" just starving for attention and if you don't provide them with it, they will stop.

Now if for some reason you have the child on a more permanent position, then consistency and showing them attention for the positive things is the way to change bad habits into good ones. This like anything will take time and it will get harder before it gets easier. Every child no matter what age has to test you to see what you will allow them to get away with. Once they know the boundary they may push (we all did!), but they won't ram the wall if they know it isn't going to budge :)