Combine the dew and spider silk in a vessel made of morning light. Stir counterclockwise until the mixture becomes translucent. Add the crushed lavender stems and fold gently -- do not break the silence of the process.
Set the vessel at the edge of the meadow where the grass meets the hedgerow. Wait for the temperature to drop below the dew point. The fog will begin to form from the edges inward, settling first in the low places where water remembers itself.
Duration: until the first bird speaks. Yield: one meadow's worth of fog, sufficient to obscure all paths and render the familiar strange.
Begin at the hour when the sky cannot decide between gold and violet -- that uncertain margin where day and night negotiate their border. You will need a vessel of clear glass, no taller than your hand from wrist to fingertip, with a mouth wide enough to admit the last light.
Hold the vessel at arm's length toward the western horizon. Tilt it seven degrees -- no more, no less -- until the interior fills with the particular amber that exists only in the final twelve minutes before the sun crosses below. You will know the angle is correct when the glass hums.
While the light gathers, speak aloud the names of three flowers that have closed for the evening. The naming anchors the twilight, gives it weight enough to remain in the vessel when the source has gone. If you cannot remember three flower names, the names of three colors will suffice, though the result will be thinner.
Stop the vessel at the precise moment the first star becomes visible. Not when you think you see it, but when you are certain. The difference between these two moments is where the twilight lives.
Store in a cool, dark place. The bottled twilight will keep for one season. When opened, it will illuminate a small room with the exact quality of light from the evening it was collected -- every shadow will fall at the same angle, every surface will warm to the same temperature of gold. Use sparingly. There are only so many twilights in a life, and each one bottled is one fewer witnessed.