If I get a chance, I like to gather some water from the nourishing rains of spring, and make Charged water from it. I leave out a big bowl overnight in my back yard to collect the water in, and bring it in first thing next morning; or at least before the sun comes out and shines brightly on it (since I’m making storm-water and not solar water).
I strain the water through a double layer of cheesecloth into an appropriate container. I like to use bottles that don’t have a metal cap for this application, as I feel that charged water (or things with similar energy like wood from a lightning struck tree, for example), shouldn’t be in contact with metal lest the ‘charge’ go out of it.
To my water I add an ounce of a high-proof, neutral alcohol (like vodka), to help preserve the mixture and keep molds or bacteria from growing in the water bottle. To this one I also added some of Sarah Lawless’s Saining Oil, since I’m planning on using this water to asperge participants during ritual, and in the consecration of ritual spaces and tools, as well as an aid to magic.
Lastly, I charged the water with my own energy, and energy drawn up through myself from the wet earth and down through me from the still cloudy spring sky. I labeled my bottle and noted the phase that the moon was in when I gathered it (Full moon in this case, about a week before Beltaine).
The kind of rainstorm (or other precipitation) that falls, the phase of the moon, the time of year, all these factors can provide quite a few waters to charge and use to various ends, limited only by the appropriateness of the forces at hand, and the imagination of the witch.