Candle magick, as it says, is doing spells, rituals, etc with a candle. Candles as you all know come in different shapes and sizes and different colors. Candles should be suited to the spell you are doing. For example, if you are doing a money spell, luck spell, or prosperity spell, you would use a green candle. For love, you would use a red or pink candle. When done with your spell, do NOT blow out your candle. This blows the magick away. Snuff out your candle with a candle snuffer, or if you do not have a candle snuffer, using something that is not flammable will do.
Before you begin in candle magick, go and research the various properties of candles and research how they are used.
Of course, when lighting your candle, you want to have it no where near flammable items and on a flat surface. If you are to put your candle in a candle holder, make sure they are not near any curtains or any tapestry that is flammable. Be very careful not to have your candle near any children if you have any or any pets if you have any. Be safe and cautious for one little candle can cause a fire.
Candle color is especially important to candle magick. Some candle colors that are associated with the Elements (if you work with them/study them) are:
Water~ Dark Blue
Spirit (Depending on Beliefs)~ White.
A white candle is the 'wild card' of candle magick. The reason I say this is that if you do not have a candle color that you need, you may use a white candle in its place. To do this, carve the name of the color on the candle. For example, if I needed an Indigo candle and I did not have it, I would carve 'Indigo' on a white candle. You should carve with a tool that is used for carving or a needle. Be careful not to cut yourself!
(I have two other posts on candles: The working candles and a specific post for the white candles. Go and look for those in the misc. topics sub-forum section.)
I hope this was able to help you.