Candle Magick is a practice as old as time, as it is great for communicating with spirits, guides, and the universe.
It is considered a kind of alchemy.
Fire of the flame, Air to feed it, Water is melted wax, Earth is solid wax.
The color of candle you use depends on your intention.
Some examples are:
Green : Money, Abundance, Luck, and Growth
Black: Banish Negative Energies, Protection
Red : Lust, Passion, Energy, Love
Various herbs, oils, and crystals can be added to serve your desired result. You can also layer on other meanings by carving symbols, runes, or sigils into candles or putting oils on them. Remember always that its your intention above all that sets the tone for your spell work.
Your candle magick should be performed in a clean, sacred space of your own.
Return to your candle at roughly the same time each night to meditate on your desire until the candle is completely used up, or for a specific number of nights.
*Reminder: Never blow out your candle once your ritual is performed. Snuff it out instead.