Practice, practice, practice!
I usually begin a weekly lesson by asking my students if they’ve practiced during the week, not to guilt them into practicing more, but to get them to think about the link between how much they practice and the progress they’ve made.
Trying to find the time, and the mental focus, to practice can be really tough - I speak from experience! But regular, focused practice goes a long way to building the habits that form the foundations of technique. If a student is trying to wrap their head around correct breathing, for example, practicing with a ‘little and often’ approach will get results a lot quicker than one long practice session.
This is true for most things we learn - we’re literally building new connections in the brain, and the more connections we have, the easier something is to do. There’s a great article explaining the science here
Eventually, with enough practice and enough repetition, something will become a habit, and our unconscious brain can take care of it - it becomes second nature, leaving the conscious brain free to concentrate on more important things like telling the story we want to tell, and moving our audience.
After all, that’s what we’re aiming for, right? That’s what all this practice is for, to do all the hard work beforehand, so that when it comes to performance, we have all the tools we need to do the best job we can.