Colors are usually applied to candles but are equally as effective when used with clothes. Like if you wanted passion and love you would wear red. Or you could burn a red candle. A combination does not mean that it will be twice as effective, but it couldn't hurt. *wink* The general colors used are as follows:
Red: health, energy, sexual potency, courage, will power, to conquer fear or laziness.
Pink: love, affection, romance, spritual awakening, healing the spirit, togetherness.
Yellow: intellect, imagination, power of the mind, creativity, confidence, gentle persuasion, action, attraction, concentration, inspiration, sudden changes.
Orange: encouragement, adaptability, stimulation, attraction, sudden changes, control, power, to draw good things, change luck.
Green: abundance, fertility, good fortune, generosity, money, wealth, success, renewal, marriage, balance.
Blue: truth, inspiration, wisdom, occult power, protection, understanding, good health, happiness, peace, fidelity, harmony in the home, patience.
Purple: success, idealism, higher psychic ability, wisdom, progress, protection, honors, spirit contact, break bad luck, drive away evil, divination.
Brown: attract money and financial success; influence Earth Elementals, concentration, balance, ESP, intuition, study.
Black: reversing, uncrossing, binding negative forces, discord, protection, releasing, repel dark magic and negative thoughtforms.
White: purity, spirituality and greater attainments in life, truth, sincerity, power of a higher nature, wholeness.
Magenta: very high vibrational frequency that tends to work fast, so usually burned with other candles; quick changes, spiritual healing, exorcism.
Indigo: meditation, neutralize another's magick, stop gossip, lies, or undesirable competition, balance out karma.
Gold or very clear light yellow: great fortune, intuition, understanding, divination, fast luck, financial benefits, attracts higher influences, male deity powers.
Silver or very clear light gray: removes negative powers, victory, stability, meditation, develop psychic abilities, female deity powers.

That's about it for the colors. I copied that right out of my Book of Shadows (a wiccan tool) which i copied out of D. J. Conway's "Celtic Magic"
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