"Rich Dad Poor Dad" is a stepping stone for me.
It's the first financial self-help book that I ever read.
Next is
"The Power of Your Subconscious Mind" by Dr Joseph Murphy.
The current for me is
"Master Your Mind Design Your Destiny" by Adam Khoo. Talk about beliefs and NLP.
All the 3 books are simply fantastic. My grades in University improved tremendously after reading the 2nd and 3rd book.