It seems to us that a good relationship between author and writer is critical to writing a good how-to book. Why would readers follow advice in a book if they did not feel like they liked and trusted the author? If you want to write such a book, it is a good idea to be very clear about who your reader is and how you want to address that person.

How-to books that hop around among first (I, we), second (you), and third (he, she, they) persons are a little bit like talking on an old-fashioned telephone party line. The voices come out at the reader from every direction.

Here is an example from Amazon’s top 100 books list:

Change rites as the mood strikes you. As long as the rite attunes you with the deities, all is fine. Don’t shut out the physical world in favor of the spiritual or magical realms, for only through nature can we experience these realities. We are here on Earth for a reason.
Do, however, use ritual to expand your awareness so that you are truly at one with all creation.
—WICCA: A GUIDE FOR THE SOLITARY PRACTITIONER by Scott Cunningham

Is this author writing for you, the individual reader, or for we, some larger group? Why does he differentiate between you and we? Why not just write for one or the other? And what does this say about his relationship to the reader? This may not seem like much, but if you look at the examples below – also from the Amazon 100 list – you will see how much more comfortable it is for the reader when the author is clear about voice – and the phone line is a dedicated one.

We, all of us:
Atoms have always existed, but it was only rather recently that we became sure of their existence, and it is likely that our descendants will know many more things that, for now, we do not. That is the wonder and joy of science: it goes on and on uncovering new things. This doesn’t mean that we should believe just anything that anybody might dream up: there are a million things that we can imagine that are unlikely to be true…
—THE MAGIC OF REALITY: HOW WE KNOW WHAT'S REALLY TRUE by Richard Dawkins, Dave McKean

We, the authors; you, the reader:
Most people think the economy will get better soon. It won’t. We can tell you what you want to hear, or we can help you enormously by showing you how to prepare and protect yourself while you still can and find opportunities to profit during the dramatically challenging times ahead. We may not give you news you like, but it will definitely be news you can do something about…
—AFTERSHOCK: PROTECT YOURSELF AND PROFIT IN THE NEXT GLOBAL FINANCIAL MELTDOWN by David Wiedemer, Robert A. Wiedemer

I, as an example:
Yet, as I thought about happiness I kept running up against paradoxes. I wanted to change myself and accept myself I wanted to take myself less seriously – and also more seriously. I wanted to use my time well but also to wander, to play, to read at whim. I wanted to think about myself so I could forget myself…
—THE HAPPINESS PROJECT: OR, WHY I SPENT A YEAR TRYING TO SING IN THE MORNING, CLEAN MY CLOSETS, FIGHT RIGHT, READ ARISTOTLE, AND GENERALLY HAVE MORE FUN by Gretchen Rubin

You, as the person to whom this book is directed:
What flows through your mind, sculpts your brain. Thus, you can use your mind to change your brain for the better which will benefit your whole being and every other person whose life you can touch.
This book aims to show you how. You’ll learn what the brain is doing when the mind is happy, loving and wise…
—BUDDHA'S BRAIN: THE PRACTICAL NEUROSCIENCE OF HAPPINESS, LOVE AND WISDOM by Rick Hanson, Richard Mendius