Some neo-druids practice meditation and
Visualization as a method of self-
Transformation, particularly engaging the imagery of the
Four Elements of the classical philosophers and the medieval alchemists. Earth, Air, Fire, and Water are considered symbolic of aspects of nature and are sometimes linked symbolically to the four cardinal directions, the four seasons, and the four stages of human life — that is birth, maturation, old age, and death. Elemental symbolism is fluid and varies from group to group. Some modern druids believe that the ancient Celts did not adopt the Greek system of four elements and prefer to use only a symbolic division of the cosmos into three realms — Sea, Land, and Sky.
Downloadable books (free):
Anonymous - Divination Spreads
Alan Wallace - Lucid Dreaming And Meditation
Aleister Crowley - Book 4 Part I Meditation