Always trim wicks to 1/4 inch before lighting. The first time you light your candle, let it burn for 3-4 hours to allow the melted wax to reach the edge of the container to prevent your candle from tunneling.
Follow the 2 foot rule - don't place a burning candle near anything that is flammable. Keep lit candles away from drafts, ceiling fans and any air currents. Never leave a burning candle unattended. Extinguish all candles when you leave a room or before going to sleep or if the flame gets too close to the candle holder or container. A candle should not be burned for more than four hours at a time. For a margin of safety, discontinue burning a candle when 1/4 inch of wax remains in the container.