One of the jobs, and even joys, of writing fantasy or science fiction writing is the creation of worlds. Worldbuilding is a tradition with inventive fiction from Jules Verne in the 19th century to the modern day, and most fantasy writers have developed their own world.
The true groundbreaker on this was J.R.R. Tolkien. Before him, writers such as George MacDonald had created settings for stories and poems, but they were only as developed as the immediate text required. A few sketched maps, a concept of the local area, and what sort of creatures are involved are as far as it went.
Tolkien took it much further, developing an entire world, with new races, animals, thousands of years of history, languages, cosmology, and much more. Instead of just the setting he needed, Tolkien designed such a deep and vast world that he could refer to ancient events, locations, and peoples. The book took on a sense of depth and weight beyond mere faerie tales and seemed almost real.
Its not necessary to build an entire world, solar system, or universe to tell a tale, but the more you create, the better you're able to make a plausible, immersive setting the reader can sink into. Especially for fantasy, having maps can attract readers who like to think about the locations mentioned in the story and their relative locations.
But drawing a map can be intimidating, especially for a new writer. Where do you start? What should it look like? Should it be done by hand? Is there some computer program?
It takes a certain level of talent to be able to draw even a simple map but even a very crude one can be welcome in books. Here are a few maps from some classic fantasy series:
|Fafhrd & Gray Mouser's world: Fritz Lieber|
|The Map of Narnia: C.S. Lewis|
|The Young Kingdoms, home of Elric: Michael Moorcock|
|The Grandaddy map: Middle Earth|
If you look at each of these maps, you can see some similarities that stand out. They're all simple line art, most of them are black and white, they look hand-drawn, and are light on detail. Even more modern maps such as these follow the same pattern:
|Game of Thrones setting|
|Sword of Truth setting|
In fact, some are so simple they seem almost silly, but that's the point. Think of it this way: if you whip up a beautiful National Geographic-level work of art with photoshop and hours of work, it will look beautiful. But it won't look like something a scribe worked up in a dusty workshop with a quill based on the reports of sailors, hunters, and scouts gathered from around the world over hundreds of years.
|Which password did I use again?|
What you want is something that Gandalf could have dug up in the libraries of Minas Tirith. It should look like a lost parchment, not a slick modern professional document. If the first thing people think of when they see it is "wow that took hours" not "that looks real" you have lost the charm of the map.
Another thing you can see by looking at these maps is that they are unfinished. What's east of Mordor? What is in that blank area south of the Flatlands? What's the rest of Narnia like? Its likely the creators have some idea, but for the purposes of your map, it doesn't matter. In fact, the more blank and unknown areas (here there be dragons) the more plausible the map looks.
Cartographers in the old days used to fade out borders and leave blank spots not for style, but honesty. Nobody knew what was out there. They worked from tips and information they would gather from travelers, particularly merchants, caravans, and sailors. The borders of continents were usually pretty well charted out by ships, but the interior was often a mystery. Leaving some parts blank makes your map see more authentic to the time period.
In a science fiction setting, you have a lot more detail at your fingers. Satellite imaging, laser scanning, and computer analysis can spit out a detailed map of a planet in short order with any decent level of technology. Yet there still will be unknown areas. Humans have been mapping and writing history of earth for over five thousand years, but we still don't know everything about our home. Leaving some areas blank not only makes your map a lot easier to make, but it results in a map that makes sense to readers.
Something else that's useful is to think small. When you create your map, start in a small area, and work out from it like ripples in a pond. This works best for world building too, but that's another topic. Create a village, then think about the surrounding area. What do the people do in the village, are they farmers, loggers, miners, fishermen? Do they need large fields or forests, do they have to have a body of water nearby?
Then you have to consider trade. Where and how do they get their goods to a larger market? Roads and rivers, canals and other methods of travel begin to spring up. What's the weather like in your little village? That will be affected by the altitude and nearby features such as oceans, mountains, and so on. Slowly, your village starts to be the center of a larger area, spreading out to add other villages, cities, roads, deserts, jungles, and so on. Each new area is like a new center of activity, spreading details around it.
Your map can spread out from a single area, giving you a more complete and organic world rather than a bunch of areas thrown together. And by doing this, your world will become more the kind of place that pulls readers into the story rather than making them ask questions about how that little village on top of a mesa gets its water.
And of course, there's your story. Obviously the places mentioned in your book will need to be on the map. If you mention the forest of Pzann and the Olestra Peaks, they belong on your map so people can get a sense of where things are relative to each other. If you're writing a series of books, or a lot of books in the same setting even if not a sequential story, then you'll want more world depicted, even if not very detailed.
Maps are usually best hand-drawn at least in the rough. You don't need anything too fancy, just a quick set of areas and basics like roads and rivers. Then you can either get an artistic buddy to lend a hand, study maps like the ones above and try your hand with a pen, or use some software like Campaign Cartographer, StarPlanet Map Maker, and Autorealm are available as are many other free or shareware systems. A short search can call up a few good lists to try out.
In the end, don't worry so much about looking like a professional and more about giving a fun map with the details your readers need.