It is important to charge your crystals with an intention. Generally, you work with the natural qualities of the stone to decipher what your intention should be. Charging crystals is easy to do, and can take as much or as little time as you like!
First things first: Clean your stone by running cool water over it, thinking about all unwanted energies washing away. Or you can place it in the light of a Full Moon for 3 days. (The day before, the day of, and the day after). You can ritualize this process if you desire. Creating a ritual is easy – the more intention you put into each step, the better.
Once the stone has been cleansed, it is open to receive your intention. All quartz crystals are considered energy “amplifiers”, so you can ask the stone “Please help me to feel positive energy on a deeper level”, or “Please protect me from unwanted energies”, or anything else that suits your needs.
A great book for discovering crystal meanings is “The Crystal Bible”, by Judy Hall, or you can find a ton of free information on the internet!