The three most important things to do as a parent is to
discipline: Setting rules and clearly stating consequences of not following those rules, and being consistent with the punishments. Also explain in a way for the appropriate age group what's expected of them and how it makes you feel when they disobey. DO NOT set a rule that their age is unable to follow. I feel that setting rules at the age when they're more likely to test boundaries and get into things ( 2 yrs and up.) is loving because they will listen to you when they get into something that could hurt or even kill them. You set the rule to always hold your hand when you cross the street, if you don't have that set as a rule and just say " Hold my hand." and they don't listen and run across the street they could get hurt.
TIP: Make an age appropriate activity game that lists rules and little velcro sticker pad or a whiteboard marker and have them mark what rules they followed that day, mark how they felt afterwards after following that rule, and give them a reward. Little rewards could be praises and getting favorite foods or getting to pick the movie to watch that night. A weeks worth of following rules you set can ensure for them a bigger reward.
Spend time with them: show them care and do activities together. So many parents are caught up in their jobs and this world. There are hardly any parents who take the time to read to their kids. I feel this is necessary because few kids feel like they are worth their parents time and love and also kids learn better when they have mom and dad helping them.
The third most important principle of parenting is; Love among yourself and your partner. So many kids, even though their parents try to teach them, can end up bad because of how their parents treat each other. Mom and dad should deal with each other in a mild way and NEVER shout in front of their kids. They should give each other a cooling off period where if one of them feels like they're going to shout or get visibly angry say calmly " May we talk about this later, or somewhere else?" and find a quiet room away from that person and think about what happened, and how to react without being unreasonably angry.
NEVER say anything bad about your partner with your kids present. And NEVER remark after your child's bad behavior " You're just like your father! " Or " Just like your mom!" This shows them your lack of respect for your partner. If you don't respect your partner, why should they? This is a very very big cause of drift in families.
Two things I think I will never do as a parent is, I will never yell at my kids in anger. Yelling isn't going to make them want to do better, it just makes them afraid of you and makes them feel you're unpredictable and explosive. Another thing I feel I will never do as a parent is, neglect them. I will do my best to nurture them and give them the best they deserve. All kids deserve the best in life they can get. It starts with parents.