Keep your wicks trimmed or they will tend to smoke which is not good for you, your walls or furnishings.
Burn candles away from drafts. A draft will cause your candle to burn unevenly, drip and smoke.
Keep candles out of strong light. It can make the colour fade.
Refrigerate your candles for an hour before burning. They will last longer. Wrap them in foil or plastic when they are in the fridge or the wick will absorb moisture and the candle will not burn properly.
Store candles in zip lock bags to conserve their scent and keep dust off.
Before a dinner party, light your new candles before the guests arrive, then extinguish them. It will be easier to light them later when the guests arrive.
Burn the candle for 1 hour per inch of diameter for longer lasting candles. For example a 4 inch diameter candle should be burnt for 4 hours at a time.
If you don't have a long match or lighter to reach a deep or high candle, light a piece of uncooked dried spaghetti and use it to light the candle.
Use an extinguisher to put candles out, or blow with your finger to your lips to block most of the force of your breath. This will prevent candle wax from being splattered around by the force of your breath. It is said that this practice is the origin of the gesture "shhhhh" with finger to mouth, used at bedtime to quiet children and put out the lights.