Sounds like you are well on your way.
I too wanted to do things differently, that is, learn better, smarter and focus on clinic issues that I knew were my weak areas. I had a lot growing up between my BSN and MSN, thus was far more serious with my studies.
I used the flashcards, jotting them down during class and carried them everywhere. As well, I recorded a lot more in grad school and listened much more efficiently.
I went part-time after my first semester. It was just too much to try and keep up being super RN in the ED and try to learn/absorb all as a NP student. My preceptors and mentors all advised part-time, to allow plenty of time to focus on my future career, giving all I could as an NP. They were right and I'm glad I changed to part-time (24hrs/week).
This allowed plenty of time at home with the family, plenty of time to read the material and re-read, create cards and type my notes from the recordings. Yes, I did a lot of redundant learning, but ask any Physician or PA and they all do this as well. I relearn even as an experienced NP now. Never hurts to review what you think you know.
I wouldn't buy a lot of books until getting the reading list from classes. One item that saved my life was a smartphone, specifically I had a Palm Tx. Just having a drug reference at your fingertips during reading and clinical, makes a huge difference. Taking the time to understand why you would give a Macrolide over a Quinolone, when to start using Lantus, what's a corrected calcium, etc. All of these are examples of why it's more important to cut back on the RN work and focus on the NP work. Believe me, your new boss is going to expect you to hit the ground running, not playing catch up between patients.
As well, I would recommend cheat sheets and prompt cards. I found two prompt cards that absolutely saved my life, one a cards cheat/scut card that a Cardiology Fellow gave me, the other, a general H&P card from ScyMed.com, both cards are from a well known author, Dr. A. Arturo Rodriguez, and he must have been around awhile, the cards card is from 1996! As you dig deep into the ScyMed website, you begin to realize the power of these tools. Good luck, I spend hours just browsing thru their offerings.
Finally, remember to be good to yourself. No one else will realize the stress you about to dive into. Take some time out occasionally to splurge, go swimming, buy a new outfit. Reward yourself for those A'! Keep us up-to-date on your progress.