Science fiction is one of the most creative genres of fiction on the market. Science fiction does not limit itself to what is possible, or even what is probable. In this genre, the best stories are the most imaginative ones.
- Familiarize yourself with the genre. Read many, many science fiction novels to get a feel for how they are written. There are humorous science fiction novels, believe it or not, as well as hard science novels, parallel world novels, space journey novels and many other sub-genres.
- Get familiar with a few standard science fiction concepts. There are a few concepts that are commonly understood by science fiction fans as being methods associated with the genre. For example, hyperspace as a mode of space travel is a well-recognized transportation concept in science fiction. Readers also widely understand and accept wormholes as a means of traversing vast regions of space. This does not mean that you should necessarily use these well-worn ideas, but rather that they are so well-established that they would not have to be explained. Understanding these transportation modes, ways to go faster than light speed and different types of space journeys (such as generation ships and suspended animation) can also help you to get through basic plot problems you encounter, and may also suggest new plot points for your novel. Reflecting on these standards can inspire you to create a new concept as well.
To use these standard concepts effectively and avoid the story becoming a cliché, they should support rather than be the focus of the story. There are lots of generation ship stories -- if you do have a generation ship, the story should be about the unique characters and action aboard the ship and not about the journey itself. Any of the standard sci-fi concepts are new again if they are used in the context of a fresh, unique story.
- Establish the rules of your written world. Every science fiction world (even if it is Earth) has certain rules that govern it. The world can have any rules you like, from the near future's slightly evolved technology, to the far future's magic-like gadgets, to rapidly advancing technology belonging to a group of moles in our contemporary rain forest. What the rules are doesn't matter as much as making sure that they are consistent. Because science fiction relies so heavily on the imagination of the writer, keeping consistent rules is one important way to ground the story and make it seem more plausible.
- Get your science right. Even if the science in the novel does not play by the same rules as our own (science fiction science rarely does), you still must know how it is different and how that changes the story. For example, if you plan to put a group of people to sleep for a hundred years, we know it can't be done currently. But even though there's no real hundred-year sleep model upon which to base your story, you do need to understand the aging process and possess scientific understanding of sleep. Otherwise, your frustrated readers will be wondering why the sleeping characters don't age by 100 years. Are they actually in suspended animation, or is it a different technology that is keeping them asleep without aging? Knowing about the aging process gives you new ways in which this can be done and will make your story that much more original.
- Keep a human element to the story. Even if there are no humans in the story, there should be some human aspect of the story that readers find compelling. You could introduce a human-alien interaction, explore a familiar ethical issue or give your aliens roughly human qualities, just to name a few of the countless possibilities.
There is no reason that a highly imaginative work of speculative fiction can't seem realistic. As long as the story is consistent and well rounded, there is no reason why the reader shouldn't be able to suspend disbelief.