I spent decades reading about writing before I took up writing as a regular practice. One of my favorite books on writing is Brenda Ueland's If You Want to Write: A Book about Art, Independence and Spirit.
First published in 1938, this slim volume continues to inspire. Ueland's list of things that all of us who want to write need to know is instructive.
You'll have to read the book to learn more, but the very best advice on writing I've ever received is Ueland's directive to "write freely, recklessly, in first drafts." She also reminds us to be "true, honest and untheoretical" in our writing. For someone with control issues who lives mostly in her head, writing freely and recklessly and untheoretically is a very tall order.
I am sometimes paralyzed with perfectionism when I am trying to write; the words simply fail to come out, and when they do, they don't do a thing for me. But really, the moment I write words, I'm a writer, and it is healing.
And I've learned to repeat over and over and over again as I write, "This is a first draft." As with recovery, just getting started, not perfection, is what counts. If you want to write, place words on paper.