Many events start out with a group vigil before breaking out into smaller teams for individual vigils. They should ideally be conducted in silence, so you should make sure there is a good separation between groups.

It's best to perform these vigils or séances in darkness. Not only does this help set the mood, but it's also said to help the spirits around you manifest. Many paranormal investigators believe that in order for a spirit to manifest, it needs to draw on all of its energy to take on a physical, or at least visible, form. When light is present in the room, surrounding energy drowns the spirit out. Occasionally, a spirit will be strong enough to overcome this barrier and manifest during the day, but generally, it is considered to be more difficult.

The effect is similar to the principle that a radio has better reception at night. You'll find that...