Mastering Astral Projection: 90-day Guide to Out-of-Body Experience by Robert Bruce and Brian Mercer is exactly what its title suggests: a 90 day program by the end of which you will learn how to have out of body experiences at will. The program is based upon Robert Bruce’s excellent book on the subject, Astral Dynamics (see below).
During the first part of the program, you will learn and practice all the fundamentals required for conscious projection, including relaxation, breathwork, energy body stimulation, trance induction and more. After 45 days of preparation, you will start practicing different projection methods for an additional 45 days. By the end of this program, you will not only be an accomplished projector but you will probably also start having lucid dreams and perhaps even develop psychic abilities. This highly effective program is how I learned to have conscious out of body experiences.