Sleeping advice

I know this has probably been asked a thousand and one times. But how can I teach my 4 week old daughter the difference between night and day? She sleeps all day, no matter how hard I try and keep her awake, and stays awake for 3-4 hours during the night!! She has no idea if the difference, and it’s a real struggle, because I find it difficult to sleep during the day so I’m exhausted! I’ve just changed her from pre made formula to powdered and it seems to have chilled her out, but not at night!!