Working candles are used whenever you conduct magickal work. Some examples of this are writing spells, writing in your Book of Shadows or creating spellbags (Mojo bags). Your Working Candle should be brand new, never used. Working candles are usually white, which is neutral, but you may use a candle that is the color of your element. If I am not mistaken, Green is usually used for Earth, Yellow for Air, Dark Blue/Royal Blue for Water and Orange/Red for Fire. You can put your candle outside in the sunlight/moonlight for 12-24 hours until it is ready to use. If you feel it is not ready yet, take a clear quartz crystal and put it next to the candle so it can clear any energies you want to get rid of. Now you think of what you normally work with in magick. Draw symbols that have to do with your workings. Draw the Triple Goddess, a pentagram, or the symbol of the five elements if you wish. It is entirely up to you what to put. To consecrate your candle after you have done what was said before, say With the Goddess and God working for me and through me, I charge and consecrate this candle for the use of positive magic and positive witchcraft only. For the good of all and according to free will, so mote it be." Your candle should now be ready to use. Some dress their working candles in many different ways. You can dress your candle however you like, with oil or a herb. There are many ways you can dress your candle.
I hope I was able to help with your creation of your working candle.
(Some information in this post is of my own knowledge, and some is from this site: http://rainbowsandraindrops.blogspot.com/2011/06/witches-working-candle.html)