Find live water. By “live” I mean it has living things in it such as healing minerals, and water spirits. This water is best found in a mountain stream, river, or at a natural spring. If you are unable to conduct the ceremony at one of these locations, get plenty of the live water and carry it back in a container for use at another location.
This ceremony is most powerful at night just after sun down or even more powerful after midnight, but before 3 am. This is the time of spirits. During the day there are far too many distractions and interferences for the spirits to have much impact or communication.
Have the all the people stand in a circle. Sing a song or make a prayer that calls in the helper spirits (Tunkasilas) or angels or whatever type of spirit being you are used to or comfortable with. Then go to each person with burning sage, cedar, sweat grass or other medicinal herbs and let the smoke cover their bodies to purify and clean away all negative energies. While this is being done some people get messages for the person being cleansed. This adds a special meaning to the ceremony.
A song or prayer for healing of physical, mental, spiritual and heart matters is appropriate at this time. After the song/prayer, the people go around in a circle speaking their individual prayers and wishes.
After this is done, everyone will lie down or sit down in the water. Or the water can be gently poured over everyone. As the water runs down our bodies it takes the impurities with it and sends them back to the mother earth for purification and reuse.
A final song or prayer to thank the spirits, angels, helpers, etc. completes the ceremony. After this, it is always good to share food.
As a note, this is another water ceremony, but it is much simpler and can be used daily. Pour water (this can be regular tap water) into a container, I use a gourd or a wooden bowl, but a simple glass would do. Walk outside and sing a song or say a prayer, then four times pour a portion of the water into the ground. Drink the remaining water so the prayers enter your being. Pouring the water into the ground is returning the life blood (water) of mother earth to her. This water once poured into the ground will travel all around the planet in underground waterways and maybe even to the ocean depending on where you live. I would suggest if you feel the urge to pray for peace or environmental concerns this is the ultimate way to send those prayers.