From time to time, and especially when you first acquire then, you will want to clean your ritual tools. This is more than just a physical get-the-dirt-off cleaning, but rather cleaning off vibrational energies from your tools. I find this technique especially usefully in cleansing divinatory tools, such as tarot cards, but it works well for any tool.
To start off, you want to set up your working altar so that you have an incense burner of some type in the East, a candle in the South, a Chalice of water in the West, and a bowl of salt or earth in the North. Light the incense and candle and get yourself into a ritual state of mind. For incense, I prefer sage or sandalwood, but any good purifying incense will work just as well. In the East, slowly wave the object through the smoke of the incense three times, saying:
In the name of the Lord and Lady, I cleanse and consecrate you with the element of Air.
If you wish, change the "Lord" and "Lady" to your specific patron God and Goddess. Now go to the South. Wave the object through the flame (or over it, if you are dealing with something flamable, such as tarot cards) three times, and say:
In the name of the Lord and Lady, I cleanse and consecrate you with the element of Fire.
Moving to the West, dip your fingertips of your projective hand (right if you are right-handed, left if you are a southpaw), and sprinkle water onto the object three times, saying:
In the name of the Lord and Lady, I cleanse and consecrate you with the element of Water.
Move to the North. Once again, touch your fingertips of your projective hand to the salt or earth, and flick it over the object three times while saying:
In the name of the Lord and Lady, I cleanse and consecrate you with the element of Earth.
Now take the object in both of your hands, and place it in front of your heart. Close your eyes, and vizualize energy coming from your hands, heart, and third eye, bathing the object in your energy. When you feel ready, cut off the energy. The object is now cleansed and consecrated. This object is now also yours. You should avoid letting other people handle it, although you may repeat this cleansing at any time, and as often as you see fit.
Other techniques
There are other techniques for ritually cleansing your tools. One way is to bury the object in the earth for one week (please remember when you buried it). Another is to immerse it in running water overnight (real running water, not your sink). A friend of mine (who is actually the one who taught me the cleansing above) is a genius when it comes to magickal herbalism, and created an elemental wash that will cleanse items as well as anything I've ever used. There are probable as many techniques as there are witches; these are just a few of the more popular ones, and what I use. Use whatever works for you, and what you feel comfortable with.