8 to 12 Months
When your baby starts to crawl, around the 8-month mark, it's time to think about setting limits. Suddenly everything -- from the knickknacks on your side table to those rolls of toilet paper under the bathroom sink -- are big no-nos.
A child this age only wants to explore (he has no concept of what he should or shouldn't do), so if you don't want him to touch something, place it out of his reach through childproofing and let child-friendly items take center stage. Experts say this is the best way to help your child stay out of trouble and makes it a lot easier to follow the rules.
Of course, many of us merely say no when we catch our little ones getting into mischief. Unfortunately, it's not a reliable discipline method for kids this age. Your child can comprehend by the tone of your voice that "no" means something different from "I love you," but she doesn't understand the real meaning of the word. Furthermore, she doesn't have the self-control to heed your request.
Use other techniques to reinforce the lesson that some things are off-limits, as Cristina Soto of New York City does. "Starting at around 8 or 9 months, every time my daughter Sonia got near an outlet, I'd say 'Aah aaah!' in a playfully scary voice so she'd stop and look at me," says Soto. "I kept doing it. After a while she'd cruise over to an outlet, point, and say, 'Aah aaah!' to me."