Now we know where we’re going to begin it can be all too easy to try and tell the reader everything about the world all at once. Too much information will slow the story down and risks boring the reader because there’s only so much information the human brain can process at once. However, it’s important to note that in a first draft none of this matters, just write it out. Sometimes when you’re writing a first draft you need all that information to help you sort out everything that is happening in your head. This doesn’t matter, it can all be edited out later on if it proves unnecessary.
How much information you include is up to you because it depends on the story you’re writing but a good rule of thumb is asking yourself, ‘Do I need this? Does it need to be here?’ An example might be that you’re describing the house your character lives in and you thoroughly describe their massive collection of CDs. It may turn out that such a description doesn’t fit at the beginning and weighs it down. But later on when the collection becomes important, perhaps another character is looking at it, the description works far better. Similarly there might be description later on in the story that in retrospect works far better at the beginning of the story. Don’t be afraid to chop and change, it doesn’t matter if your second draft is completely different from the first, editing is about making any changes that you feel are necessary.
Of course, I should mention that although I’m talking about establishing a world it doesn’t mean only fantasy worlds but any world. Even a world based on reality needs establishing because although it is the same as the readers’ world the reader needs to be able to see it in their mind’s eye. Simply saying it was a typical street in London or Delhi or Sao Paolo doesn’t work because it doesn’t give a sense of the place. You don’t need to explain every little thing but at the same time you shouldn’t assume that they know what a ‘typical street’ looks like because everyone sees the world differently and every part of the world is different. Once again it doesn’t mean you need reams of description, generally speaking a few choice phrases scattered around can slowly build up a picture of the individuality of a place. If you feel you haven’t quite locked down the setting in the first draft it can be added to during edits when, having finished the story, you’ll likely have a much clearer idea of the world than you did in chapter one.
When you are describing the world at the beginning, or anywhere in the story, it’s important to bear in mind what kind of scene you’re writing. Is it a slow one where you can take your time? Or is it a fast action-packed one? This will affect the amount of description that works in the scene because description of the environment slows the pace down. For example, if your protagonist is being chased you don’t want to stop for a long description of flowers in the park. However, if your protagonist is sitting in the park quietly contemplating then a description of the flowers might work better.
Read around different genres to get a feel for how world building is used and what you think works best. It might be helpful to read a story set in the ‘everyday’ world and a novel set in a fantasy world to compare how they introduce readers to their worlds. Then experiment with description and placement to see what you think works best for your introduction. As with any aspect of writing setting doesn’t need to be perfect first time and can be honed later on.