In a candle spell, we first charge the candle (or empower it), directing our own energy into the candle. This, like raising our energy before the spell, is very necessary. Without charging, the candle basically has no power to bring you what you need. This energy we direct into the candle is then released when the candle burns, going into the world to create the change we desire.
While charging a candle for a spell, many Wiccans, myself included, anoint the candle at the same time. Anointing is simply rubbing oil, or some other substance on the candle, intending to help direct our energy into the candle. When performing a spell to attract something, or performing a positive spell of any kind, the candle is held between the index finger and thumb of your receptive hand (the hand you DON'T write with), and oil is rubbed on the candle from the tip to the center- and then from the bottom to the center with the finger and thumb of your projective hand (the hand you DO write with).The candle is never rubbed back and forth. By rubbing inward from the tip and inward from the bottom, we are "drawing" our intended goal to us.
To charge a candle for a spell to banish or dispell negativity of any kind, we anoint the candle from the center outward. Hold the candle with the index finger and thumb of your receptive hand and rub the oil on with your projective hand- from the center to the tip, and from the center to the bottom. Again, never rub back and forth.
Almost any type of organic oil can be used for anointing (I wouldn't recommend motor oil!). I prefer olive oil, but any vegatable oil can be used, or an essential oil can be used as well. Generally, if I do use an essential oil, I use one that corresponds with the spell I am perfoming. I will explain herbal, oil, and incense correspondances on my Herb and Incense page.
While anointing the candle, focus on the goal of your spell. Then imagine sending the energy you raised into the candle- flowing from your chest, down your arm, and out your finger tips. Focusing completely upon what you are doing is necessary in any spell. Don't allow your mind to wander. Focus on the outcome of the spell, and directing your energy.