The most effective teaching tool you have is your positive attention as a parent. Become a pro at catching children being good and learn to ignore inappropriate behavior when you can. The more you can give children the attention they want when they behave well, the less misbehavior there will be to worry about. Positive discipline is not spoiling a child.
Children become spoiled when parents give too much attention when children demand it.
Catching children being good is giving them a smile, a touch, or a few words of praise for good behavior as often as you can throughout the day - it is not giving privileges or presents in response to tantrums or whining. That is just behavioral noise that is best ignored. Children need praise and encouragement like a plant needs water, so water them regularly.