If you've invested time and money in golf lessons it is obvious you want to improve your game. Your actual lesson is only 45 minutes to an hour so what you do between lessons is crucial to your long term improvement.
First of all you need to be realistic. Any player when making swing changes is going to hit some bad shots. This is not the time to panic and give up on the changes, especially in the early stages. Right now you are working on a technique, so it is a mistake to judge your progress by the immediate results. Your focus right now is on your technique - the results will come later.
Rather than hitting balls nonstop make lots of practice swings. Sense the feeling of your new technique rather than thinking about it. Work with a mid club like a 7 iron and tee the ball up slightly. I suggest 3 or 4 practice swings focusing on technique then make one swing with a ball. Begin with 1/2 or 3/4 length swings at a smooth pace.
Keep in mind that great swings are not created overnight - they require a lot of work. Persevere with your new technique and you will be rewarded with better shots and more consistency.