You just start it. Beware - this game is notorious for showing you in your face that whatever doesn't work in your base is YOUR problem, you made a mistake, pro

You just start it. Beware - this game is notorious for showing you in your face that whatever doesn't work in your base is YOUR problem, you made a mistake, probably plural, probably too basic to fix. So prepare to start over multiple times. It's my at least tenth attempt in 5 years right now. And it's lots of fun!