I think the first thing you need to keep in mind is that you should be very careful not to practice in bad technique. All the practice in the world is not going to help you improve your ballet if you are not making sure you are doing it correct.
If there is a special part of your technique that you have real problems with, the reason is probably because you did not master the correct technique when you first started with that step.
To start with, make sure you are getting your entire barre work perfect. Do them carefully concentrating on the correct technique. I promise you, you will see an improvement very soon. The best of course, will be to get a good book and a good video to show you exactly how you need to do everything.
Here I can recommend a good book such as The Ballet Bible. In it you will find photos of correct as well as incorrect technique to help you recognize bad technique and how to correct it. There are also videos with a complete lesson to help you. This will take care of the biggest danger of practicing at home, practicing in bad technique.
So if you are wondering about "How Can I Improve My Ballet" get the Ballet Bible to help you with the problem of how to improve ballet.
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