Having a good story to tell is key to success. Having characters tell the story is your keys to the kingdom.
Developing characters in sci-fi and fantasy requires work. It begins when you identify the qualities of characters that move you as a reader. What intrigues you is likely to intrigue others who read your stories.
With Sci-Fi and Fantasy landscapes, it is essential you establish your world is possible. The sooner a reader decides to accept your vision as “real,” the quicker the suspension of disbelief occurs. Now the reader can settle down and enjoy the tale.
Characters should establish this attitude. No matter how alien, weird, or incredible the location, for those living in that place, it is normal. By demonstrating this attitude of normalcy, you set the stage. The more difficult your world may be for a reader to accept, the more ho-hum the characters must treat the “exceptional.”
You have an entire novel, perhaps a complete serial to convey your mythology; your world-building. Do not try to jam it down a reader’s throat. Work with characters within a setting to set up the location and events which make it important. Build your characters, and let them build your world for the reader’s imagination.
We do not relate to technology or how it can change our lives. We do not relate to magic in its many forms. We do relate to people. Characters have the ability to engage us. Things and abilities may impress us, and even excite us, but caring about a character keeps us entertained. We need characters in our life, even the alien and altered.
Step 1 in character building is to make sure your characters interact with their world (your vision) in a natural, normal manner. Use them to introduce the time, place, and unique situations essential to establishing your plot. Do not narrate your reader into boredom when you have the tools of conversation and observation available.
Step 2 will cover creating the starting point in character development.