Last week, commenter Mary De Bastos told us that "I'd love to write someday, and have ideas all in my head but so don't know where to begin... can you write a post for beginning writers? and how to get started?"
Why, yes. Yes, we can.
It could be a very short post, even, since my advice for
very beginning writers is:

1. Buy a notebook and a pen, and carry them around with you, and whenever anything catches your attention, or you have a passing thought that deserves more than a passing thought, or your brain goes "wouldn't it make a great story if...", or you find yourself lying awake thinking about something, anything at all:
write it down. If you can manage to make writing a habit, you're off to a great start!
So if that's what you need to get started, you can stop there and go buy your notebook and pen. I tend to be long-winded, however, so I'm going to keep typing, and if you want to keep reading, I have more tips for dealing with the fact that nothing's ever as simple as it should be.
2.
Be gentle with yourself, and your work. Was it Gwendolyn Brooks who said, "I know that I have to write a thousand bad poems to write one good one--and that I couldn't have written the good poem without writing the thousand bad ones," or something similar? (I keep googling to find the exact quote, to no avail.) Anyway, whoever said it and however they phrased it, it's true. Especially when starting out, give yourself tons of space to write badly. In fact, as you're starting out, don't even ask yourself (or--and this is important--anyone else) whether what you're writing is good or bad. At this point, all that matters is that you're writing, and enjoying it.
Side note: while you're working on writing out all those ideas, you're going to get frustrated by how different they are on the page than they were in your head. That's fine--it happens to all of us. This is why you need space and gentleness and patience for yourself. Keep trying, you'll figure it out--and even if it never comes out just right, you'll learn a lot from the process.
3.
Read, read, read. Read the kinds of books you're interested in writing. Get out of the habit of reading to find out what happens, though, or you won't learn nearly as much as you could: I tend to read everything twice, once for fun and once critically, to see what the author did and whether it worked for me or not.

4.
Do not, do not, do not rush into showing other people what you've written. Especially when you're starting out, that never goes as well as you think it will. You need time for yourself, to write for fun, get a handle on how you feel about your own work, and generally develop a really thick skin, before you start letting other people weigh in. However,
5.
Find a community. Writing is a lonely sport, and frankly, it's kind of a weird thing to do. Seek out other people who do it--particularly, but not necessarily, other people who are interested in the same kind of writing you want to do, and also just starting out. Check out colleges, continuing ed programs, and community groups to find literature classes or book clubs or, maybe, a group for beginning writers. Eventually you may want to take a writing class or find a critique group, but even before that, it's good to surround yourself with other people who think books are important.
6.
Read some more. One of my favorite things about being a writer is that other writers, generations of them, have created on paper (and in cyberspace) the kind of community I was talking about.
Lisa Greenwald regularly posts favorite quotes on writing; I also found
this great page of writing quotes while I was looking for the Gwendolyn Brooks quote.
Writers also write whole books about writing! Here are some of the Longstockings' favorites about writing and life:
Bird by Bird by Anne Lamott: probably the best book for getting started, as Lamott really knows how hard it is!
If You Want to Write by Brenda Ueland: a little old-fashioned, but very democratic
On Writing by Stephen King: not so much a
favorite as the book that provoked the most interesting arguments when we were in grad school!
Escaping Into the Open by Elizabeth Berg: I haven't actually read this one, but it's Jenny Han's favorite, so it's gotta be terrific
Writing Down the Bones by Natalie Goldberg: a Zen approach to writing, and a must-read. Even if you don't end up adopting her practice, it's a great thing to try
A Moveable Feast by Ernest Hemingway: actually, I'm not sure if this is a Longstocking favorite or not, but it's where I've gotten some of my best advice about the process of writing
Also, John Gardner's
The Art of Fiction, while not a "writing life" type of book, includes an appendix of writing exercises that I have found extremely helpful. I don't agree with everything he says, but the exercises are fun and stimulating, and will make you a better writer
Okay, that's my advice, based on what I've learned over the last ten years. The floor is open in the comments section: what advice would the rest of the Longstockings, and our readers, give to a writer just starting out?
--Kathryne