I know that everyone is completely different in what works for them for studying so I suppose you want to keep that in mind, but I used the Saunders book and answered I think literally *all* of the questions in the book and accompanying CD. I really feel like answering all of those questions was a very huge contribution to passing my boards (last week! Yay!). I have also heard that the NCSBN Review Course is helpful and the cost is based off of how long you plan on using it. (link here: NCSBN's Review for the NCLEX-RN® Examination v7.0.1 - Students - NCSBN Learning Extension
I have several friends who did not pass on their first try and one thing they had in common was that they overwhelmed themselves with content and crammed until last minute. Obviously studying and understanding of content is important, but I would say that I am super happy that I took the time to give my brain some rest before the test. I quit studying 2 days before the exam and feel that that helped as well. Said friends who did not pass the first time now say that they wish they would have let their brain rest.
I wish you good luck and good results! Relax, you've done this before so the stress of the unknown is now gone. Hopefully there was SOME sort of nugget of help in here.