When it comes to creating a proper setting there are three questions you will have to answer: what, when, and where. This is where your timeline and the culture of your story are defined. A single mistake in setting can be enough alone to destroy your mythos and knock your reader right out of the story.
Imagine your protagonist, the good guy, tramping through the bush of a Jurassic era jungle. Huge dinosaurs scream in the near distance and the horizon is hazy with the smoke of an erupting volcano. Suddenly he hears a chirping and a shrill beeping. Turning a corner he comes face to face with…an Apple Iphone stuck in the crook of a branch.
What’s the problem here? Well nothing if this is Jurassic Park Part Six, but if it’s a story about a family of man living in a prehistoric valley then everything’s wrong. So, when it comes to creating your setting, take the time to think about the times, places, and people your character will encounter. Just taking the one extra step of knowing which types of plants can grow in your area and at what times of year, can make all the difference between having an engaging narration and one that begs your reader to explain and overlook your mistakes as they read.
In N.H.I., I have both real and imagined elements that make up my setting, but the key is to cause the created portions to fit seamlessly in with the real.