Using:
Place the candle away from windows on a stable non-flammable surface.
The optimal time for one-time candle burning, from 3 to 4 hours, allows you to avoid the formation of a tunnel (in one session, the upper layer of wax should melt to a depth of approximately 1-2 cm).
Regularly shorten the wick to about 0.5 cm. Do not throw pieces of wick or other substances into the wax.