What actually helped improve your baby’s sleep?

Hi all — Newton team here! We have a question for the parents who've been through the sleep trenches.

We talk a lot about mattresses, but we're genuinely curious about everything else that helped.

Outside of the crib setup, what actually made a difference for your baby's sleep? A bedtime routine that finally clicked, the right room temperature, white noise, a specific sleep sack, adjusting nap timing, feeding schedule changes, or something totally unexpected?