Kelly Sue: Okay, this is an inordinately lengthy answer where I’m going to get into the What, the How and the Why. Deep breath. BUT. If you’re not feeling up to it, Kieron Gillen has a great “How To” fumetti right here. If you’re not that interested in the sausage-making, just go there.
All right. Who’s still with me?
Just you? Okay, then.
Most periodical comics are still sold through specialty retailers (often referred to as the “DM” or “Direct Market”) who, unlike traditional bookstores, are not able to return unsold stock. They have limited budgets, limited shelf space and new comics come out every Wednesday! So they have to be very selective about what they buy and in what quantity. They each have their own complicated algorithms for how they place their orders, but it essentially comes down to their needing to buy what they’re pretty sure they can sell. There’s no McDonalds of comic book stores — most of these shops are “mom & pop” businesses being run by people who love the form. They’re not in a position to put their necks on the line every week. For the most part, they have to play it safe.
Safe tends to mean the top selling titles (“A-list” heroes, “A-list” creators) get ordered in quantity and everything else (“the Midlist”) is ordered sparingly if it’s ordered at all. (Remember: they can’t order everything. They just don’t have room–in the store or in the budget.)
Publishers, in turn, use the order numbers from retailers to determine whether a book is going to continue, and for how long. Remember: these books are not returnable, so from the publisher’s perspective, each order is a sale. As such, they can have their sales figures on a particular issue before the book ever hits the racks. That’s how a book can get cancelled before it ever comes out. And folks, that happens. Not infrequently.
Right here I could bore you with how publishers seem to be reacting to the buying habits of the retailers by publishing more of the A-list titles we talked about before (and or “double shipping” them, which means putting out two issues in one month) and really pruning back the midlist. Can’t blame them, really. That’s how capitalism is supposed to work, right? Right.
Okay, I’m going to move on rather than opine on why I think this is a mistake and how it’s resulting in a pruning of readership as well. Honestly, I don’t have an MBA and I’m not in charge of any of these companies. My opinion on this particular issue doesn’t matter all that much and I could well be wrong.
However! I do have a horse in this race. Several, actually. And the best tool I know of to combat the ouroboros of it all is the pre-order.
When you pre-order a comic with your local shop, you are registering your intent to buy said comic. That’s the What.
If the shop knows you’re going to buy, well then, that’s a no-brainer for them, isn’t it? Most stores will reward a guaranteed purchase with a discount. And at some stores the discounts get deeper if you subscribe to (or “pull”) a title, and deeper still if you pull multiple titles. If they get enough pre-orders on a book, the book has “buzz” and they may take a chance and order a few extra copies for the shelf as well. Orders numbers go up, customer is happy, publisher is happy, book exists for at least another month. EVERYBODY WINS!
So now we know the Why.
Let’s talk about the How. For the purpose of this instruction set, I’m going to assume you’re brand new to this whole process. In fact, I’m kind of writing this for my mom and her friends. (Hi, mom. Hi, mom’s friends.)
If you want to jump in the deep end and go all hard core, you’ll shop from the PREVIEWS catalog . PREVIEWS is the catalog from which your local comic shops (“LCS”) order their comics – you can purchase a copy (Yes, we are an industry that requires our consumers to buy the catalog. In fairness, when you see it you’ll understand. It’s huge.) at your LCS and fill the form out directly from there if you want… BUT if you’re new it’s overwhelming and I don’t recommend it.
Let’s say you heard about a new series on Tumblr and you got a .pdf and you really liked it. You want to keep buying the book and you want to make sure it keeps coming out, so you’re opting to pre-order it. (Thanks, YOU!)
Find your local comic book store. This link makes it pretty easy. Just enter your zip code and you’re golden. (If you’re not in the US or Canada, I’m going to be of little help on this one but if anyone wants to comment below with tips for finding shops outside the US/Canada, I will cut and paste into this article later.)
Drop by. Most stores are going to be delighted to see you–why wouldn’t they be? You’re a new customer! 
Start a conversation! This is really the whole point of this exercise – to get you in a store and to let the store know you are interested in a particular book/character/author.
Find out what the store’s policy is on subscribing to a title or, “opening a pull box.” What that means is that you’re putting in a standing monthly order for a certain book or books. Policies vary store to store, but if there are a couple of titles (or, ahem, a favorite author) you know you want to read every month, you can “subscribe” and your store will set aside a copy for you every time one comes out. THIS IS GREAT FOR EVERYONE, for a multitude of reasons, but I’ve gone long so I’m not going to expound much here. Most stores will have form for you to fill out to open and pull and most store will let you cancel your subscriptions at any time. Ask.
In an effort to make preordering easy, sometime creators or publishers will produce a decorative Pre-Order Form for their book and distribute it online. We do this for every issue coming out. (Find them over on our calendar entries.) They’re fun, but not necessary.
I think that’s a far more complete answer than anyone wanted, but this, my friends, is my way.
xo, Kelly sue
 “Previews” is the comic book industry’s catalog. Previews is published every month and is literally a catalog of all the comics (and statues and magazines and whatnot) that will be available for distribution to your local comic book shop from the distributer “Diamond” three months from the date on the catalog. Got that? Readers can use the Previews catalog pre-order form to order titles (or toys or whatever) through their retailer–not through Previews. That’s a little different than how we tend to think of catalogs working. I just wrote a whole big thing using the Victoria’s Secret catalog as an analogy, but the whole thing seemed overcomplicated so I deleted it. Previews also has a website and a users’ guide.
 IF THE STORE IS NOT HAPPY TO SEE YOU, LEAVE. Most comic book stores are fabulous places that will want to make you feel welcome and bring you into the fold. If you experience anything less, leave. Give your business to a good shop, or if there are no other options in your area, go digital or mail order. A brick and mortar store is ideal because it fosters community and it’s fun. But it’s not the only way to go. And there’s no reason in the world for you to be treated like anything less than the gem that you are, so if your local isn’t welcoming to you, walk away.
Pre-Order Post Addendums!
As predicted, I’ve learned a few things since I made this post. Here they are, as I understand them. Anybody who wants to correct me, please jump right in.
I’m told many stores have a minimum numbers of titles that you must subscribe to in order to open a pull box. I imagine that’s to deal with limited space…? I’m not sure. Regardless, if you want to subscribe to just ONE title and your store doesn’t offer that option, TFAW.com does. Detailed instructions are available in that link. I was surprised to see that MidtownComics.com has a 10 title minimum for their subscription service. I’m guessing there must be costs involved that I’m not aware of…? I always want to better understand the business, so if any retailers out there want to educate me, please do! 
 I have to say I’m kind of heartbroken at the notion that it might be difficult for a new reader to subscribe to a single title. It seems… like an additional barrier to new readership at a time when we desperately need to be growing out audience. Did you know that Marvel offers subscriptions directly through their site? They do!