Let’s start with world building. Keeping a record of what your world looks like, feels like, smells like, and sounds like is only part of your story. Depending on where the world is, you may need to establish rules--meaning the world isn’t of our world as we know it.
For example, if you’re creating a world where the sun burns out or is destroyed, researching theories of how it would affect the earth would need to done. Or say your characters are in space. Probing for information about current travel in space or theories of future machines that would make it possible, would be a good idea. Of course once that information is obtained, writers can take it and twist it any way they want.
There is always an element of truth in any fictional writing.
Where to begin...Write EVERYTHING about your WORLD even if the information written down is not used. Readers do not want to be bogged down with too much information. The only information needed is what moves the story forward and is necessary. My story took place in the Okefenokee Swamp in Georgia. I researched the plants and wildlife, the landscapes, and the history. Some I used, some I didn’t use, some I cut in the editing steps.
Getting started with your world.
What does it look like?Is there foliage/trees/dessert?Fantastical?Real?
What kinds of smells are there?
How is the air?Is it heavy?Is it hard to breathe?Is it salty?
What sounds would be heard?Nature? Space?
What makes this world different from reality?
What’s the mood of the world?Everyone happy?Oppressed? Gloomy?
Are there animals?Real?Fictional?
Does the world have cities, towns, kingdoms, leagues, quadrants, etc?