Soy wax does not burn as hot as paraffin wax, so soy candles require a thicker wick, which does not combust 100%. After each burn, trim the wick to 1/4 to 3/8 of an inch in length to minimize soot and remove any mushrooming of the wick left by the previous burn.

When lighting a soy candle for the first time, allow the wax to pool all the way to the sides of the container. (Pooling is simply defined as melted wax. The initial burn of any candle should last as long as it takes to get the melted wax all the way to the edges of the jar - about 1" per hour.) This will give you maximum fragrance and minimize the amount of wax remaining on the sides of the container. If you don't allow the wax to pool on the first burn of your soy candle (or any candle), you may get "tunneling", which means the wax simply burns down the center of the candle, leaving wax on the side of the jar.