Think of discipline as a form of teaching, not a form of punishment.

Think of discipline as a form of teaching, not a form of punishment.
Your child needs to learn how to get along with others and stay safe. He's an eager student, but the most important lessons — sharing, patience, cooperation, caution — will take a few years to sink in. As his main teacher, it's your job to reinforce the lessons with consistency, patience, and compassion.
Consistency is especially important for toddlers. If Mom's computer was off-limits yesterday, it should be off-limits today. And don't worry about repeating yourself. A toddler may need to hear something literally a hundred times before he gets the message.
When he does misbehave, he doesn't need a lecture. Give him a firm "no," perhaps with a quick explanation such as "you could get hurt" or "that's not a toy." Then redirect him to a more desirable activity. Toddlers have short attention spans, so he'll probably be happy to move on.

Time-outs can be helpful, but few children understand the concept until they're at least 3 years old. For a younger child, time-outs are confusing and frustrating. If your child is old enough to understand time-outs, use them sparingly and limit them to three minutes or less — just long enough for your child to get control of himself. Put him in a "naughty chair" instead of sending him to his room — you don't want him to associate his room with punishment. Consider sitting with him. He'll probably calm down faster, and you could use the break, too.

No matter how badly your child is behaving, hitting shouldn't be an option. Spanks and slaps teach children to be afraid of their parents. And even though you would never intend to hurt your child, it's easy to lose control when you're angry. If you feel like hitting your child, give yourself a time-out until the feeling passes.

Discipline doesn't always have to be negative. Praise your child when you "catch" him being good, like sharing a toy with a friend or picking up a mess. He'll learn that he doesn't have to misbehave to get your attention.

Finally, make it as easy as possible for your child to do the right thing. Try to avoid putting him in situations he can't handle. For example, don't take him on long shopping trips when he's tired and hungry. And don't surround him with things he's not allowed to touch. If his world is cluttered with temptations, you'll spend all day saying "no." Try to maximize his opportunities to play and explore but minimize his chances to get into trouble.