Eli's starter kit for being an effective human:
These are the books that I recommend to everyone who is on a path of learning to use their mind more effectively than the default. All of these are foundational for my personal practice.
The Less Wrong Sequences by Eliezer Yudkowsky
A wide-ranging discussion of formal and applied epistemology, covering philosophy of science, cognitive psychology, the hard problem of consciousness, interpretations quantum mechanics, evolutionary biology, metaethics, Artificial Intelligence, and what it means to think well as a human being. This "book" has changed my life and my thought process more than anything else I've ever read.
[Note: Despite the word "sequences", I wouldn't worry about reading these posts in order. Start with some post, and follow up on all the hyperlinks that seem interesting to you.]
Getting Things Done: The Art of Stress Free Productivity by David Allen
I reread this book ever few years. it outlines a flexible system for staying in control of one's attention, rather than having one's mind constantly yanked about by one's environment. Along the way it highlights a number of important principles of human cognition with broad applicability.
Focusing by Eugene Gendlin (audiobook version)
Focusing is a core introspection technique that I use on a daily basis. CFAR used to recommend the Audiobook (which is how I originally learned), rather than the printed book, because the audiobook can guide you through the exercises. If you prefer a physical book, you should read The Power of Focusing by Ann Weiser Cornell instead.
How to Measure Anything: Finding the Value of Intangibles in Business by Douglas W. Hubbard
This book is effectively "how to do quantitative empiricism, in practice."
Nonviolent Communication: A Language of Life by Marshall Rossenberg
Most people's relationships are full of conflict and emotional coercion. NVC is a simple framework for getting our needs met more honestly, more cooperatively, and more efficiently. It takes skill and practice to be able to reliably hold the the spirit of NVC, but if you get there you can pretty much avoid ever having a fight with someone you care about ever again, if you want that.
The book is mostly examples of NVC in practice. Reading through those examples is helpful for getting a handle on the spirit of NVC. One can perform the steps without the spirit, "weaponizing NVC", as well as holding the spirit without any of the steps, which generally works. But the first two chapters are only 8 pages long, and outline the basic algorithm. So in a pinch, you can start with that.
[Less important] Superreading for Success by Ron Cole
The summer after my senior year of high school I read a bunch of books on speed reading and speed learning. Of that survey, I thought this was the best one because 1) it focused on comprehension first (most speed reading programs do increase reading speed, but at the expense of understanding, which defeats the purpose), 2) it included a technique that you and start using immediately (and which I still use to this day), and 3) it included tests for measuring your progress. I still do the eye-hop exercises, on a spaced repetition schedule. This is less relevant now, since almost all my reading is on my laptop, for which these techniques are less relevant.
Also, I believe this book touts a bunch of basically false woo (learning styles, photoreading, etc). Don't take everything in it seriously.