According to an article in the June 2012 issue of Parent magazine, much of the heavy lifting of discipline comes before misbehavior happens, not after. Having a few well-thought-out guidelines will result in fewer instances where you need to be the bad guy.
Step 1: Be Realistic Setting reasonable expectations means first understanding what your child is developmentally capable of. For instance, 3-year-old lack the maturity and social awareness to share consistently. If you insist on sharing at this age, you'll only end up fighting. For more info on age-appropriate behavior, go to parents.com/behavior-expectations.
Step 2: Know Yourself Only set rules that you're willing to go to the wall for every time, like no hitting. You may dream of a world where your kids make their bed each day, but if you know you'll give in when they push back, scrap bed-making as a requirement or amend the rule in a way you can get behind (such as saying that beds must get made but you'll help).
Step 3: Make It Official Call a family meeting to collaborate on a few essential house rules that everyone can agree to. Let kids contribute every step of the way, offering ideas, decorating the list, and choosing a spot to post it. Then, if they break a rule, you can direct them back to the agreement they helped create.