We usually describe rooms by what we see: the light, the furniture, the colour of the walls. But a room is also what it smells like, and scent is often what we remember of it.
Here are a few things we've learned about letting fragrance into a space.
Start with one. A single cone is enough for most rooms. Let it burn down, then wait a little before deciding whether you want more. The fragrance keeps moving after the smoke has cleared.
Mind the air. A gentle flow of air carries fragrance through a room; a strong draught scatters it. While the cone is burning, keep it away from fans and open windows. Air the room afterwards.
Choose the place. Set the cone on a heat-resistant surface where it can't be knocked, away from curtains, shelves above and anything that could catch. Never leave a burning cone unattended.
Choose the moment. Fragrance is most noticeable as you arrive: when you come home, when guests walk in, when a room has just been tidied. Light a cone a little before, and the scent will already be part of the room.
Let the room rest. We stop noticing the scent of a room we spend time in. Leave a day or two between uses in the same space, and the fragrance feels new again.
Most of all, keep it quiet. The aim isn't to fill a room with fragrance, but to change its atmosphere a little.