When you first start doing science lessons, do them right along with your child. Work right alongside them, talking with them about what you’re doing.
You’ve got to teach them “best practices” like reading the instructions, figuring out what materials to gather, and how to execute a real science experiment, not just make a mess and do whatever seems like a good idea in the moment (like watching YouTube videos that show “science” projects that are downright dangerous).
You can write out a list with a standard framework for how to do science experiments, just like a real scientist does. I have complete instructions for how to do this here on my website: www.SuperchargedScience.com/journal