As soon as you can, start a “commonplace book.” 

A commonplace book is simply a place where you keep things – or everything. 

Heck, you don’t even have to call it that. 

Anyway, Ryan Holiday calls it that and wrote about his commonplace book, here. 

I use Evernote as my commonplace book.

Notes can be made for everything you want to save and all notes are able to be categorized and tagged by topic.

In addition, everything is searchable. 

Specifically: Every book I read becomes a note in Evernote where all the passages I want to remember are stored.

Later, I make a new note for each passage, and each individual passage is tagged by topic. 

Good grief, I wish I had started my book when I was 18. 

The point is to not just read and experience life – and then press on with something else. 

It can be incredibly valuable to codify your experiences, your thoughts, and specific passages that stand out to you as you read. 

Over time, as Holiday points out, themes will come up and ideas and thoughts will be able to be more easily tied together. 

Knowledge is not worth much if it does not change your thoughts and your behavior. 

And it is less likely to do either if it is not easily accessible and organized. 

A commonplace book is a great place to start. 

I love you.