For this impromptu you're best off writing about a specific place, somewhat in the mode of James Galvin in The Meadow. That means I'd like you to spend this writing time trying to compose two or three separate short passages set in a certain locale of your choosing.

To do that you're going to need to do some sort of imaginative out of body traveling. I recommend that you close your eyes firmly but not tightly, let your body relax and your arms hang limply, and take a couple of deep breaths. Feel yourself start to rise as you inhale deeply and on the fourth or fifth inhalation imagine yourself rising from your chair and sweeping upward, out of the room, out of the building, high into the sky. In your mind look down and select a locale to hover above that is familiar to you, then glide towards it, floating overhead and observing what you see from a bird's eye view. Look closely, trying to remember what is below you and what its colors and textures and shapes are. Swoop as low as you need to go to see clearly and thoroughly. Take your time and hover where you have to. Then rise up and circle around and take another pass at the landscape or setting. This time, notice that the landscape has changed. It's still the same place but something has altered it, perhaps the presence of living actors. Glide closer to them, shrinking yourself and becoming invisible, so that you can hover over and about them, see the landscape or setting from their perspective. See what they see, listen to what they say, try to remember. Now soar up once more until the landscape is out of sight below you and very gently feel yourself settling back into the building, into the room, into the chair, into your conscious self.

Open your eyes and write about what you have seen.

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