Regarding advice to prepare well. In my opinion, you need multiple sources of information to cover the topics. I recommend videos, self-directed study preparation options (Thor is one example), discord discussions, practice questions (any), and any audio you can track down. I used the official ISC study guide then used other sources to get more details. The study guides were a great resource, but I also used a wide variety of sources across all the domains and studied each and every one in detail to help fill in gaps. I ran thru as many practice questions as I could find via ISC or other sources.
It was a process that took me a few months, and I was dedicated to this task 100% full-time. During the test, I concentrated thru the entire exam, especially the first questions - as it is adaptive, and the better you do in the beginning, it helps if you get them right, you may have less questions (minimum is 100 - max is 150).
It is a process for sure..no quick way in my mind for the amount of material - then again, if you have the experience already, may be faster. Here is wishing you the best in your CISSP journey!