Since last year, I have developed this habit of creating notes while reading a book. Mostly, I read books on digital devices, either laptop or phone. Crunching the pages, I keep highlighting important passages I come across and then prepare well formatted note in Evernote.
On the same line, I read this book, How to Win Friends and Influence People by Dale Carnegie, made an all-in-one comprehensive note, that summarizes the entire book in 25 pages. Sharing the summary here. Also, it's available for download in pdf version.