Positive self-esteem is fundamental to a child's emotional and psychological well-being. It significantly affects their ability to form meaningful relationships, and how successful they are academically and, ultimately, in their chosen career.
Be consistent. Children thrive on stability and predictability. It allows them to feel safe and secure. Children also need firm boundaries, so they have a clear understanding of what they can and can't do. It's really important to ensure that you are consistent in enforcing those boundaries. Otherwise, children receive mixed messages, and this makes them feel uncertain and insecure.
Focus on the behavior and not on your child. Avoid labelling your child "good" or "bad", and focus instead on the behaviour that is in issue. If a child is regularly told that they are "naughty" or "bad", then they are likely to start behaving in accordance with that label. Conversely, labelling a child "good" is unlikely to produce the intended result, because the label is neither specific nor measurable (more on this below). Instead, focus on describing the behaviour, not the child. Be specific about what it is you are encouraging, or wishing to deter. It is also helpful to reassure your child that, irrespective of their behaviour, you will always love them unconditionally.
Treat your child with respect. The best way to encourage your child to treat their parents, and others, with respect, is for you to model that behaviour in your dealings with them. A child who is treated with respect is more likely to be respectful to others.
Validate your child's feelings and emotions. Children can become distraught about things that seem incredibly insignificant to us as adults. Nevertheless, it's important that we acknowledge the validity of our children's emotions, and provide them with comfort, reassurance, and guidance as to how to manage their "big feelings". This is essential if children are to ultimately learn how to self-regulate their own emotions.
Give your Child a Choice. Wherever possible, give your child a choice rather than dictating what they must do. This is far more empowering for a child, and affords them with a sense of responsibility for the decisions that they make, and their outcomes.