Building self-confidence can be as easy as changing the way your praise your child. Instead of saying “Good job!” be as specific as you can. Try saying, “I like that you really stuck with that until it was finshed.”
I also love when I overhear parents giving praise, especially if the act wasn’t a success. For example, “You almost got it!” or “I like how you tried hard to zip your jacket by yourself.” Your words are teaching them that it is okay to not master something on the first try and that you want them to keep trying.
So many of our new preschoolers come to us not wanting to do an activity if they can’t do it perfectly. This is very developmentally appropriate, but we remember our goal is ready our kids for school. We want them to have the courage to begin and learn from a mistake or two. Start building that confidence intrinsically and watch them tackle harder and harder situations with confidence.