Bringing up of child is one of the most challenging jobs. Being a parent you have to be very careful in raising your kids as you are the role model for your children. Your way of speaking, body language, behavior, expression everything is absorbed by the growing kid. It starts reflecting on the development of self-esteem.
Being a parent, praising the child on their accomplishment of any task right from childhood develops their self-confidence. Task big or small or of any kind, letting them do independently makes them bold and stronger. Avoid passing any comment, sarcastic remarks, or comparing them with another child. Be careful with the language which you use.