Write the living bits first, then paint the house around them. That's my take, anyway. I used to spend paragraphs describing the exact layout of a room before anyone moved or spoke, and the whole thing just died on the page. Now I try to let the scene unspool from a character's goal or a specific conflict. If someone's desperately searching for a key, the scene becomes the frantic shuffling through papers, the feel of dusty drawers, the growing panic that blurs the edges of vision. The setting emerges from the action, not the other way around.
Sensory details are huge, but they have to pull double duty. A 'damp, cold room' is fine, but 'the chill seeped through his socks like the memory of that last argument' does more work. It sets a mood and ties back to character. I'm always asking if a detail is just wallpaper or if it's reinforcing the emotion of the moment. The scent of coffee isn't just world-building; it's either a comforting anchor for a homesick character or a bitter reminder of a long, lonely night.
Finally, and this might sound small, but I pay attention to the rhythm of objects. A quick sequence of actions—grabbing a coat, slamming a door, keys jangling—creates a fast, urgent pace. Lingering on a single object, like the slow drip of a faucet, stretches time and builds tension. Controlling that pace through what you choose to describe, and how long you spend on it, is the invisible hand guiding the reader's heartbeat through the scene. It's less about building a set and more about conducting an experience.