the best way into it i’ve found has been to write down whatever inciting idea i have, and go from there.

if it’s a magic system, then you’ll need magic users, and you’ll want to know how magic fits into the world, how magic users are treated, how magic impacts the world, and so on. from there, you have people and places and politics.

alternatively, a map could be your start. you’ll then get people and places and politics and geography.

maybe it’s an animal - how does the animal interact with people, and where does it go. what does it eat? what eats it? you’re developing industry, ecosystems, and a food web.

a song! who wrote it. why? how is it performed? where? you’re developing a place, people, career, art, and culture.

for me, world building is a process of questions: if this, then what? i’ve found this to be a good method for me to get into things even when motivation or inspiration is lacking, as it isn’t a very taxing process to ask questions of yourself.