Here are some recommendations for preventing -- or at least reducing -- bad behavior.
Establish and provide the necessary structure: rules/expectations and consequences.
Set limits; be clear and consistent.
Your responses to your child's behaviors/misbehaviors should be predictable, not random.
Organize and arrange the home environment in a way that will optimize the chances for success and avoid conflict.
Anticipate problem situations and avoid them.
Set up routines and adhere to them as closely as possible. For example: morning routines for getting ready for school, mealtime routines, homework routines, and bedtime routines.
Try to keep calm and avoid discipline that is reactive and not thought out in advance.
"Child-proof" the house: Remove items or objects you don't want your impulsive/hyperactive child to touch or play with.
Anticipate stressors and frustrating expectations and work around them.
Avoid fatigue -- your own and your child's.
Focus on your child when he is behaving appropriately. Make it your goal to catch him doing things right with high frequency and praise. Identify and specifically point out the positive behavior(s) and positively reinforce them at those times. Parental approval is very important to most children. Knowing that you are aware of his efforts to exhibit self-control and that he can earn your approval and other awards is a strong incentive.
Try to give your ADHD child as much of her own space as possible.
Plan ahead which behaviors you will work towards increasing and how you will reward (positively reinforce those behaviors).