Most nursery inspiration is designed for photographs, bright, styled, and full of charming objects. A nursery designed for sleep optimizes the opposite direction, and nearly everything that matters costs little or nothing.
Darkness is the biggest upgrade
The single highest-impact change in most nurseries is making it darker. Streetlight and summer-evening glow keep rooms twilight-bright at bedtime. Proper blackout, even the taped-cardboard test version before committing to curtains, is the cheapest sleep improvement in the catalog. For the light that remains, warm and low beats cool and bright, a dim amber lamp for feeds rather than the ceiling light.
Calm for the eyes
Soft, muted, low-contrast colors read as restful, dusty lavender, warm cream, gentle sage, night blue. High-contrast patterns and busy wall decals are stimulation, which is a fine feature of a playroom and a bug in a sleep room. Same for clutter, open shelves of colorful objects give a curious brain a menu. A basket with a lid is a sleep tool.
Calm for the ears
Hard floors and bare walls make a room echoey, and echo makes every household sound sharper. A rug and curtains soften the acoustics noticeably. The finishing layer is a steady sound bed at a gentle volume from across the room, which evens out whatever the rug cannot. A warm pad like the one on this page turns a silent, echoey box into a room that sounds as soft as it looks.