It is clear to most readers' eyes that Sci-fi involves what people called Utopia and Dystopia. Classifying this two features of Sci-fi deeper, "Chain of Sci-fi Elements", the first step to a good Sci-fi stories, would be obtained. "Chain of Sci-fi Elements" is basically a base that formed Science Fiction. It is written in the form of "what if + theories + reality".
(To easily remember this, I think of the word "wither" from "What If + THEories + Reality. So yeah, wither, a word with negative connotations but useful in Sci-fi .)
Having known the basic elements of Sci-fi, writers have a good chance to start their story. At the starting point, a good Sci-fi writers would list down all his/her ideas regarding the plot they are creating using the Sci-fi Chain Elements. This could be in the form of questions, bullet points, etc. always beginning firstly with the elements "what if". A good listing would involve complete data of the story, esp. if you are creating your own world such as its geography, laws, living things, etc.
- What if cars can fly?
- What if humans are mutants?
- What if the earth is not round?
- What if humans can teleport? or can walk on water?
- What if time machine exist and time could be altered?
When the listing is done, the second step could be pursued which involves applying scientific theories to your planning and ideas that will made up the plot of the story. It is important to remember that a good Sci-fi plot doesn't only include theories but logical theories, something that your readers find in between the line of realism and imagination. Creating a world where humans walk upside down will make the reader goes "What!", resulting them to lose interest in reading the rest of your story.
Furthermore, following your own laws would be a very important rule in writing Sci-fi stories. This proves your complete understudying regarding your imaginary world in which the readers might see positively. A world where human can fly with technological wings would be ridiculous if the people in it fall in air. The same thing applies, a world where gravity is 0 would be weird if its people walk on the ground. By this, here, the writers have to stick with their own rule and follow them.
After applying the second element into the story, the last element would be added to secure the invention of the imagination as well as the plot. The element "Reality" allows you to compare your world with the world humans are living at this period. As a result, the goal of Sci-fi story is dug out here, which is "Dissociation." A good question to ask oneself as a Sci-fi writer would be "How alike is my imaginary world to the world I am living right now?". If the imaginary world created is so much like the realistic world, Sci-fi readers would find the story unappealing.
In letting the readers know more about your world, you might want to include some background information about it such as how the world is formed and why does it work that way, how things work and how your characters interact with each others and to things. However, putting these information in one big paragraphs or chapters or listing down facts and laws about your new world wouldn't make your story a good Sci-fi Narrative. This step could be achieve perfectly through out the plot by telling the activities of your characters and describing your imaginative world physically and theoretically through your characters.
Describing how your world look like:
“They stood in a vast courtyard several times the size of a football field, surrounded by four enormous walls made of gray stone and covered in spots with thick ivy. The walls had “to be hundreds of feet high and formed a perfect square around them, each side split in the exact middle by an opening as tall as the walls themselves that, from what Thomas could see, led to passages and long corridors beyond.”
Excerpt From: James Dashner. “The Maze Runner.” iBooks.
Describing one of your character which is a monster:
“Thomas shrieked before he could stop himself, jerked away from the window—but the thing 54
bounced backward, leaving the glass undamaged.
Thomas sucked in two huge breaths and leaned in once again. It was too dark to make out clearly, but odd lights flashed from an unknown source, revealing blurs of silver spikes and glistening flesh. Wicked instrument-tipped appendages protruded from its body like arms: a saw blade, a set of shears, long rods whose purpose could only be guessed.
The creature was a horrific mix of animal and machine, and seemed to realize it was being observed, seemed to know what lay inside the walls of the Glade, seemed to want to get inside and feast on human flesh. Thomas felt an icy terror blossom in his chest, expand like a tumor, making it hard to breathe. Even with the memory wipe, he felt sure he’d never seen something so truly awful.”
Excerpt From: James Dashner. “The Maze Runner.” iBooks.
Describing how your characters interact and history of your world:
“The woman looked back and forth between Thomas and Teresa, then let out a sigh. “It’ll take a while before you get your memories back, if ever—we’re not scientists, we have no idea what they did to you, or how they did it.” Thomas’s heart dropped at the thought of maybe having lost his memory forever, but he pressed on. “Who are they?” he asked.
“It started with the sun flares,” the woman said, her gaze growing distant.
“What—” Teresa began, but Thomas shushed her.
Just let her talk, he said to her mind. She looks like she will.
Okay.”
Here, it is clear that the writer's imaginary world started when a disease called "The Sun Flares" occurred. Also, the readers are able to see how the characters posses the power of telepathy.
Excerpt From: James Dashner. “The Maze Runner.” iBooks.
Lastly, to improve your understanding further regarding Science Fiction, reading Sci-fi books is one of the best activities you could do. Others include imagining other worlds, predicting the future, build a deeper understanding in scientific theory and inventing some laws you think might be unique to a universe.
"While science fiction often addresses contemporary issues, that doesn't mean you should scour today's headlines for ideas. Current events become old news very quickly. Instead, let ideas come to you by keeping your mind in "what if" mode as you experience the world around you. Be well-read but also widely read, in fiction and nonfiction, in news articles and magazine features covering a broad spectrum of topics (not just those relating to science and technology). Use television news programs and documentaries as a springboard for "what if.""
Writing World. Science Fiction: The Literature of Ideas. Last Modified: 2003. http://www.writing-world.com/sf/sf.shtml.