No matter for what medium, if you're planning on telling a story you're going to have to do at least some world design. There are tons of different theories on how to go about making a world all over the place, and in time I may even go more in depth into the intricacies of it, or at least the intricacies of how I do it. For now however, I think I'm just going to go over some of the basics, as well as three questions you want to keep in mind whenever you are world building. So let's get started then.
Things To Keep In Mind
Whenever you are designing a world there are three questions that you want to be asking yourself with every decision you make. Keeping these in mind will make the whole process go just that much smoother, as well as help to keep you on task for whatever purpose you are making the world.
Question 1: Why Is This Interesting?
This is the actual design question you want to be asking yourself with everything you put into the world. "Why is it interesting?", or with different wording "Why does it matter?". This question should be easy to answer in the beginning stages of world design, when you are placing the larger pieces that will work as your foundation. As you go through and get closer to settling on finer details however it may become harder and harder to answer. Keep in mind, in some cases an answer of "it's not interesting, nor does it matter" is perfectly acceptable. However, if you are honestly saying that about something, then why are you putting it in the world in the first place?
Interesting however can have a number of answers. Something can be interesting because of the impact it has on the world's history, it could be interesting because of some plot relevant event that will happen in the story, something can be interesting for any number of reasons, but knowing why this particular thing is interesting when you place it in the world will help you with fully fleshing it out.
Question 2: Does This Make Sense?
We're not looking at real world sense when we ask ourselves this. If we were interested in the real world, our story would take place in it. However, our story doesn't take place in the real world, it takes place in this fictional world that we're building, and as such we only care if it makes sense in this world. A better way of wording this question might be "is this consistent?", however something can make sense for the world and be totally inconsistent with the rest of it. For example, somewhere in your world may be a super high-tech bunker full of alien script and weaponry, this is inconsistent with the rest of your world, but knowing the full story for the setting (as you do) it can make perfect sense to be there.
This is probably the most important question to be asking yourself as you're building your world. You especially want to ask it after you have answered question #1, as the reason you made something interesting might not make sense for the world. At which point you either need to re-examine the item you made, or the world itself to see which should change (or change more if both do) to make the item fit inside it.
Question 3: How Does This Affect My Story?
Almost everything you put into the world can have some impact on the story you are trying to tell. While it may be minimal, it is still something you need to keep in mind. This is more likely to happen when you are designing the areas that key parts of the story are going to happen in, however it is something you want to keep in mind. Take that bunker we used in our example for Question #2. Where that bunker is is going to impact your story, do the people who live nearby know of it? Do they have some of the weapons? If it gets revealed to them, aren't they going to want what is in it?
Another example would come from a choice of government you put into a country. Now if it's a monarchy, when the protagonists show up, they need only to ask a favor of the king to get what they need from him. If the country is ruled by a council, they may need to prove to the council that what they want is fair and right.
Whatever the case, whenever you put something into your world, ask how it may affect the story you are trying to tell. If it doesn't, great! If it does, well, make a mental note and keep that in mind when you actually get to telling the tale.
With those three questions alone, you already have the big part of how to make a world. Why is it interesting? Does it make sense? How will it impact the story? Keeping those three things in mind will make everything run smoother and go faster. However, I did in fact promise you more, so let's move on shall we?
Two Things To Keep In Mind
Before you start world building there are two things you need to keep in mind. One of them is fairly obvious, the other is a little less so. If you don't keep these in mind though in the beginning, you may be overwhelmed by the mountain of work before you, or upset later on.
The first thing is that world building is a LOT of work. Worlds are large things, and they're complex by nature. Even something as simple as the world for a shooter game could have hundreds of pages of information on it. More if you include concept art as part of the design journal. If you want to truly make a living breathing world, you need to be prepared for this. For example, my game Greymoore, in it I'm stealing ideas from all over, and as of right now I have roughly 30 pages of single spaced work on it. Some of you are saying that's not very much, others are thinking it's more than you'd ever need for an RPG where you need to adapt to players on the fly. Fact is, that 30 pages consists of a brief over view of Greymoore, and then a quick write up going a bit more in depth into the various races. Even with that, that 30 pages is still missing the over view that goes more in depth into the four human kingdoms that are on the land. It also says nothing of various myths and legends, there is no write up for history. Even with how brief I am trying to keep things as I work along on it, there is at least another 20-30 pages that needs to be written for it, and Greymoore is just one continent on the world. Is it really any surprise that most Role Playing Game companies have 200-300 page books of setting material for various places?
However, that world building is a lot of work is the obvious part of world design. The harder, and less well known, part of it is that world design is very much an iceberg enterprise. What I mean by this is that the people who read or play through your story are likely only going to see 10% of it, if even that much. The other 90%+ will remain beneath the surface of the water, unknown and unseen. Don't let that discourage you however, because that other 90%+ will still show through. It will show in how the 10% that people see all makes sense, it will show in how quickly you'll be able to answer questions about things. That 90% or so keeps everything afloat, and while it may not be seen, it is still needed right where it is. Look carefully at some games you've played recently, you can generally tell which ones had serious world design put into them, there are less things that don't make sense, more things just feel right. You can definitely tell when what you see is just the tip of the ice berg, and when it represents all the work that has been done.
That out of the way, lets actually get into some world design.
I know what you're thinking, "I'm building a world to have a setting! Why the hell do I need to start by thinking about the setting?". The answer is because setting is a lot more than place. It is also the when. In this case, it is basically answered by asking yourself "What kind of story are you going to tell in this world?" Are you going to tell a High Fantasy tale of adventurers fighting to save the world against an awakening evil? Perhaps a more Dark tale of men working to bring their Emperor's favor to them, and his disfavor on their enemies. A more modern day espionage type thriller like Jason Bourne and James Bond? Perhaps you want to tell a sci-fi or space fantasy story where countries are actually planets and aliens exist. This is the most important question to answer when you are world building, because if you don't know the answer, how the heck do you expect to make a world for it?
The rules are different for making a world for a High Fantasy and a more mundane historical setting. If magic is going to by flying willy nilly wherever it wants, it is going to show in your world. If space travel is an every day occurrence for even the poor, then you are looking more at building a universe than a planet. Not that that is a different seminar, it's still world building, but it is an important difference. You need to know the "when" for your story, and by that I don't necessarily mean year, but other things we generally associate with 'when', things such as the Tech Level for the world/universe, how populous it is, the status of magic or magic like things (for example, the Force in Star Wars), races aside from humans.
What Is The Story?
This is tied heavily to setting, but where as for setting we were looking at the "when" and "type" of world we needed to build depending on the story. Here we are more seriously looking at the kind of story we want to tell. This is more as a focus place for our work, at least in the early stages. No matter what you do, some things are just going to end up more fleshed out and detailed than others. With this, we're looking to make sure we know what needs to be more laid out, and where we can be a bit more lax with specifying, and more just know the gist of how thing should work.
For example, is politics going to play a large role in your story? If so, you need the government structure, and the specifics of the various governing bodies well fleshed out. After all, their interplay and machinations are going to be featured in your story, and so you need to know more about it. Who hates who on the council? Who likes who? Who is in it for the bribes? Who is still earnestly trying to do their job? By comparison, a war story with little political involvement doesn't need all these details. Most of the council can pretty much remain nameless. However, in the war story you need to have the borders and bordering lands between the countries more well defined, and other little things become more important as well, such as just how self sufficient for food is each country? and how much do they depend on trade for keeping everyone well fed?
All of this shapes your world, and in truth everything is important, however you could spend years working on all the little details of a world and never be ready to do anything with it. Not that there is anything wrong with this, but if you want to use the world, you need to focus on what is truly important to you and get that done. The rest can be worked with as it comes up in the crafting of the story, but the further you get from your focus the more ok it becomes to just have a general idea and not specifics ready to go.
One Race? More?
This was touched on very briefly in the earlier part about setting, though that was more in the vein of "are there multiple races", this is the more serious question of "if there are multiple races, what are they?". Knowing you have multiple races is all well and good, but before any real world building can be done you need to know who all needs a home first. So, what races appear in your story? Where do those races live? What do those races look like? How do they interact with each other and the other races? Are they friendly?
In High Fantasy, it is traditional (since Tolkien) to put the Dwarves in the mountains, and the elves in the forest. This is actually fairly commonly held to, the Elves sticking to the trees and the dwarves to elevated ground. Do you want that? It's ok to follow tradition, just as it is ok to try and buck the mold. It was in direct response to a critique on BioWare's Dragon Age: Origins that for Greymoore I moved the Elves and the Dwarves around, I wanted to try and make a world without it.
What's great about setting this question down and planning it out, is even with something as simple as "Elves live in the forests, Dwarves in the mountains, and Humans on the plains" you've actually done a fairly large chunk of world design. You've set at least three kinds of environments, Forests, Mountains, and Plains, and you've established who lives on each of them. From there you just need to visit the races, giving them some culture and breathing life into them as a species will help designing their areas of the world, and from there you work your way down into the finer detail of things.
There are many finer details to go into on world design, but from here you have a fairly good starting point, and as I said in the beginning, everyone does it differently. That being said, I want to leave you with two thoughts to keep in mind.
1) Everything is cliche - this is true for story telling in every genre. When was the last time you read a truly original story? If you tried, could you simplify the plot down to a different story? I bet you could. The fact is that human beings have been telling stories for hundreds upon thousands of years. Even if you've never read a story like yours, odds are someone out there has thought of something like it, or told it. This isn't something to be discouraged by, it's just something to keep in mind. If everything is cliche, you don't need to worry about your plot or world being cliche now do you? This frees you up to focus on other things, your own little twist on the cliche that makes it yours. Something to makes your version of it stand out from the crowd. Trust me, you'll be able to do it, probably without even realizing it.
2) This is an example given to me by a teacher years ago. Picture an empty jar. Now fill the jar with large rocks, is the jar full? Are you sure? What if we try getting small rocks in there. Those will fit right? Alright, now it's full right? Not at all, we can add sand. That's small enough to fill in the small gaps and fill the jar even more isn't it? After the sand, we can pour in water. There, now the jar is full. This is a lot like how world building works. You want to start with the big things, and work your way down. If you start with the details, you won't have room or time for anything else. So start big, and when you've crammed in all the big things you can, add something a bit smaller, and smaller, and smaller until you are forced to pour water in to get anything else in there. In the end you have a world, a jar filled up with large objects that support, and in turn are supported, by all the finer details that make up the world.