I love charging my crystals monthly. Every full moon I will take ALL of the crystals out and put them on my deck so they can soak up the moonlight. I usually speak over all of the crystals, or write down the intentions I have for them. I start off with giving thanks/appreciation then I say...
For the people that receive these gifts I want them to also receive Love, Peace, Happiness, Kindness, and Prosperity.
There are so many ways to cleanse and charge your crystals. To cleanse mine I use a spray bottle filled with moon water or waterfall water. I use the spray bottle because some crystals are not suppose to get wet. Also because I have so many of them it makes the routine go faster.
Other ways to cleanse or Charge your crystals:
Salt
Smoke
Water
Moonlight
Sunlight
Earth
Visualization
I chose the Moon method for no other reason that I just love the moon. Pick which best fits you and don't forget to set your intentions.