We have developed a Mind Map to help students when studying for the CISSP exam.
You could find it here: https://cycubix.com/wp-content/uploads/2019/01/CISSP-Domains.pdf
As I understand this mind map is just about topics of CISSP exam. It should be even more beneficial to provide similar mind map about content of CBK. For example 'Crypography' > 'Algorithms' > ['Symmetric' > ['DES', 'AES', ...], 'Asymmetric' > ['Diffie-Hellman', 'RSA', ...], 'Hash' > ['MD5', 'SHA-2', ...]].