"One belief nearly every culture seems to agree with is that fire represents the ultimate power and ability to purify. It represents spirit in it's purest form, the manifestation of Goddess or God and the vehicle by which to reach them."
"Candle Magick Workbook"
by Kala & Ketz Pajeon
I've found candle magick to be quite effective. The steps to preparing a candle for magick are:
Defining your goal.
Meditiate on what it is you desire. Envision, in as much detail
as possible, what it is you want. Consider how you want to attain
your desire, and from what source. Spend as much time as
necessary on this step, as it is the foundation of the rest of
the work.
Selecting the color.
Using color associations, select the color that best aligns with
your intent.
Dressing the candle.
Candles are dressed by imbuing them with your intent. It is done
by visualizing your desire, as specifically as possible, while
anointing the candle. Here's the technique I use: inscribe the
candle with the power word derived from your intent. Hold the
candle horizontally while facing the Quarter that is most aligned
with your intent. Hold the candle in the middle and anoint the
candle, stroking from the middle outward if your intend is to
cause increase, from the end toward the center if your intent is
to cause decrease. Anoint the candle with consecrated oil, your
spit or your urine.
Make the lighting of the candle the magickal work of your ritual. Time the ritual, as usual, by lunar phase and astrological coorespondance. Repeat the ritual as required by the spell.