Things You'll Need
Instructions
Begin thinking of your campaign in terms of Genesis. In Genesis, the writer describes each reality being created. First, there is land, then water and sky, then trees, animals, and finally people. So, take that bird's-eye view, and create your world. Decide its shape. Is it a globe? Perhaps it is flat, as the ancients thought. Are there continents? How many? Can you pick three words to describe each continent? Its not necessary to begin making maps at this point. You don't need to know what the entire world looks like... yet. You just need to know that there is something else out there that the players may one day get to.
Next, think about the sky, the overarching themes. Does your world have a unique property of some sort? Is it an evil world, like Ravenloft? Does it have some unique mineral, such as in Red Steel/Mystara? Are the oceans water-based, or perhaps they are blood, tar or acid-based. Is the air breathable, or do the player characters need to have a magic item to allow them to breathe? Do all arcane spells require a droplet of blood to cast?
Take all of your notes up to this point and summarize it in one paragraph. For example:
Populate your world. You need to decide what sort of creatures inhabit your world. For the sake of your players, you may wish to automatically insert the standard PC races from the Player's Handbook. From there, decide who runs the show. Are humans the dominant race? How about dragons? Orcs? Halflings? Are there great sea beasts in all of the waters? How about winged races? How common are monsters?
Move on to thinking about the city/town/village that the Player Characters will start in. What is the distribution of races? Is it primarily humans, or some other race? Is it an urban setting, or rural? Create names for at least 7 or 8 different businesses (inns, taverns, magic shops, etc.) Wouldn't you rather have your heroes walk into "The Eye of the Beholder" or "The Wand of the Wizard" instead of "a bar?"
Now, you need to get your players to buy into your game. The best way to involve players is to LET THEM WRITE THE STORY. This is probably the most important step. If you skip this one, you will cheat them and yourselves out of HUGE role-playing opportunities. Give them a handout with specific questions about their character. Make them keep a copy of the answers to these questions with their character sheet. In doing so, you've opened up the door to all sorts of adventure opportunities, ones that will be involving for the PC, not just for the DM. For example, you can take the party along on a quest for vengeance with the Barbarian, or help the Druid defeat a rival order of evil druids. Perhaps the paladin will have been raised by a sorcerer, and be asked to do something against his idiom.
"The world of Colona is a slightly oblong globe. There are six main continents. Tur is the largest and contains the most variety of geographical features. Urcho is to the South of Tur and is something of an Oriental setting. Roflenia is a large island just to the east of Tur, is a bastion of evil. The remaining three continents are undeveloped. The setting for this campaign, in the beginning, is the continent of Tur. Colona is unique in that there are less than four hours of daylight each day."