Do you know that I can *still* remember corrections given to me by teachers from 20 years ago? I still try to apply them too (never did get them right!). I was taught to write down corrections after every class so that they would become solid in my mind and also so I wouldn't make the same mistakes twice. A journal can be especially helpful if you're taking with several teachers. One may suggest an arm or head correction while another focuses on your core. By writing it all down, it will reinforce your memory of the correction and also get it into your brain for an application of it somewhere else.
Here is a tip from Pointe Magazine:
"As ballet dancers, our days are chock-full of classes and rehearsals--which makes it difficult to keep track of all the important corrections we receive from teachers and coaches. Try keeping a dance journal. After class or rehearsal, spend some time reviewing your corrections, and jot them down in a notebook. Doing so will help you process and retain the advice--and the less time you spend re-fixing old problems, the more you can work on polishing the details. Soon, you'll be able to conquer whatever you've been focusing on, be it a triple pirouette or that tricky Odile variation."