What inspires you?
-A type of story?
Winning a race with honest and dishonest competitors? Fighting your way to the top in an organization? Going on a quest to find the treasure or rescue someone? Explore something? Get the girl/guy?
-A setting?
A fantasy empire? A galactic confederation? Detroit? The wild west? Ancient Rome? A haunted orphanage?
-What kind of conflict do you want to present to the player?
Fighting? Making strategic choices? Social interaction?
-What would you like to describe?
People? Buildings? Guns? Ghosts?
-What kind of atmosphere would you like to write about?
Romantic? Creepy? Military? Paranoid?
-What do you want to focus on while writing?
Facts? Descriptions? Atmosphere? Dialog?
With the game I am writing it worked like this?
Main inspiration was the setting (A magnificent fantasy empire) and the story (Try to become emperor/empress).
I already had a fairly detailed setting, and had been thinking of using it for a board game where players try to become emperor.
So the conflict will be mainly social (intrigues, strategic alliances) with some military style conflict. I envision court scenes here, people who care about things like etiquette and honor,
but also things like assassination attempts, a duel or leading your troops in a desperate action, of course dressed in some gorgeous uniform.
I like romance so I want to include that (I can see a formal ball with all the characters splendidly dressed, illegal meetings with forbidden lovers in lush gardens etc).
Thins I like to describe are social customs, buildings, landscapes, making the setting come alive.
I want an atmosphere of wonder and awe for this great empire, with growing tension and paranoia when things come to a point.
And I was focusing on description, but found that my game worked better if I included more dialog.
So I would say, start with stuff that really inspires you, whatever it is, and work from there. If you are thinking about parts of your game when you’re not working on it, you’re on the right track.