Always trim the wicks to 1/4" before each burn.
When using your candle for the first time, after trimming the wick to 1/4", let the candle burn until the wax has melted all the way out to the container. For the cleanest performance and to avoid 'tunneling', burn 2-4 hours at a time.
Never leave a burning candle unattended.
Keep candles away from direct sunlight and at room temperature.
When finished with your candle, either re-purpose the container for something useful around your home or remove the remaining wax and recycle.