I got a 99% predictor on my ATI. I did LOTS of NCLEX-style questions. I have the NCLEX Mastery app, and I just did questions any time I could. If I had a free minute, I did questions. It's about learning to eliminate at least 2 of the 4 options in the multiple choice questions and learning to evaluate the SATAs.
I got the Saunders NCLEX book for NCLEX review, and I actually wished I'd had it for all those other nursing school tests. It's great at teaching you content AND how to approach the questions.
Practice, practice, practice. Good luck, and I hope this helps!