Material used:
Official study guide (read thru whole book, gave me good idea what are covered by the exam)
Official practice exams (use it to find my weak areas)
CBK reference ( I quickly skimmed thru at very late stage of my study just because I had time, but still helped me to find some knowledge points that I didn't know)
CISSP All-in-One Exam Guide (better written, better formatting then official guide)
Official Learnzapp app (good to measure my readiness)
CISSP mind map series by "Destination Certification" (recommended, very helpful to give you an overall review of each domain, and how different components and concepts fit into bigger picture)