There are many types of "projections" going by different names:

MENTAL PROJECTION- Where the practitioner projects just his Consciousness to some other place, beyond the physical body. It's similar to a day dream only much stronger. You see a mental picture, like watching a movie, but there are no senses per se, taste, feel, hearing, smell etc.

ASTRAL PROJECTION- This is where the Consciousness & the Astral body separate together from the physical body. The practitioner has use of all fives senses plus those used by the Astral body. You may have a sense of flying or floating. Vivid dreams are often natural AP during sleep. It's perfectly safe. Nothing can enter the physical body while on an Astral projection as only you have the exact key.  At any sign of danger the Astral body is "reeled in" rather quickly.
 
ETHERIC PROJECTION- This is where the Consciousness, the Astral body and the etheric body separate together from the physical body. The ectoplasm of the Etheric body can been seen other. The physical body is reduced to a state of near catalepsy during the projection and must be protected from sudden shock or disturbance as there is a rare occurrence of physical death.

BILOCATION- This is where the Consciousness, the Astral body, the Etheric body & the Physical body are in TWO different places at the same time. This is only be used by advanced Magi and then rarely. It involves time & place distortion with a host of other things.

Mental projection is by far the easiest. Just focus the consciousness anywhere the will directs. Astral Projection requires a little more. There as many techniques & systems as there are people. Here are some guildelines & methods:

METHOD 1
In a quiet place. Sit in a straight backed chair, up against a wall or on the floor with spine erect. Relax, get comfortable. Inhale & exhale slowly a couple of times. DO NOT FALL ASLEEP!! Use 2/4 breath to start, that is; empty your lungs, easily, then inhale to a mental count of four<use your pulse as a guide>, hold <using the abdominal muscles, please, not the throat> mental count of two, expel in a four count, pause for a two count, then inhale to a four count etc, etc.

Picture an image in the mind's eye of a yourself in a ball of light about 3-5 feet away from you. Continue, slowly, rhythmically while focusing your attention on the image in the mind's eye see it clearly then shift your consciousness or point of awareness ...awareness of self, selfhood; the observing I etc. to the ball of light. Including the senses first touch, move your Astral feet & arms, then hearing, then smell, then taste & last of all when you have your other senses plugged in open your eyes and look around.

Each sense further focuses your point of awareness in the Astral body.

Astral sight doesn't depend on the physical eyes. The reason it is listed last on the list is practical. Sometimes for novices the act of opening the eyes in the Astral body triggers a reflex of opening the eyes in the physical body, without the other senses to anchor it the consciousness shifts back to the physical body and you lose the AP. Don't worry about your Astral sight at the very start work first on being sure of shifting the consciousness. That is the first step to success. The rest of the senses MUST follow. If you have to break it down even further work on hearing, smell, touch or Small Astral body movements one at a time first. Then work on sight.

METHOD 2
Start a mental projection and will your Astral body along.
 
METHOD 3
Imagine that your Astral body is separating from your physical body out the head chakra. You will sense a rapid vibration with a rising or floating sensation let it happen don't block it. When complete check your five senses in the described order.
Using the Astral body requires only that you mentally shift gears into it, no matter what method you use. Astral projection takes patience, practice & persistence.
Several things govern how quickly you can gain mastery;
  noises & distractions
  how relaxed you are
  breathing technique
  how well focused you are
  achieving the mental imagery necessary
  transfer of consciousness
  practice

"Astral Projection" is not one experience but a complicated amalgam of many types and levels of experience. AP experiences can be very sharp and clear, foggy and dreamlike, intense, mild, convincing, and confusing all at once. The common modern view of AP is that is has three (or four) basic forms; Mental, Astral, Etheric, (and rarely Bilocation). However, my experience is that there are hundreds, perhaps thousands, of variations of typical "astral travel" experiences, and that breaking them up into a few categories is more convenient than accurate.

Two of the most common reasons for not achieving a clear AP are foggy imagery & problems with shifting Consciousness to the Astral body. First the image in the ball of light must be clear & fixed. You must have a clear mental image of the Astral body to begin with. Second, the Consciousness must be fully shifted or transferred from the physical to the Astral body!! It shouldn't be shuttling between the two. It's a very common problem. But you can't drive two cars at the same time! <Grin, at least I can't> This may show up as poor Astral vision or partial or full loss of Astral senses. Sort of like poor TV reception with static & snow. Probably because of uneasiness about the unknown. Relax!! Your physical body will be just fine, really! Remember you can't swim hanging on to the side of the pool!!!! Let go!!! Trust me<grin>.

The single most important factors shaping the nature of the AP experience are practice & "Instructions" for the "voyage" given by very deep areas of the subconscious mind, "co-ordinates", if you will, that the projecting "Selfhood Program" uses for guidance in this journey through all the possible universes. These
"co-ordinates" can be suggested to the one pointed or focused mind through ritual, meditation, visualization, and many other techniques.

Without training, and developing the strength of the "psychic muscles", most people aren't able to give adequate co-ordinates to the focused mind. They are in the position, one might say, of being able to turn their psychic computers on, but they are not yet able to load in a program that takes advantage of the computers powers. The thing just sits there and hums blindly, they have some interesting thoughts or twists of perception while they do their practices, but don't usually make the shift.
The "trick" of astral projection lies in the TRANSFER OF YOUR POINT OF
AWARENESS...awareness, selfhood; "the observing I", it is "like" a vortex, an 'atom' of consciousness, which "rides" the physical body. It is not the Ego, not the "higher self"; it is more like a natural force, or quality, in the way that "weight" is a quality of gravity.

One of the keys is focus & intensity. You should become oblivious to everything except transferring your point of awareness, complete & undivided attention, focus or consciousness. Use your other senses as a check list, in the order described. Anxiety or fear of the unknown often causes problems...like swimming or riding a bike, RELAX. You won't fall or drown! If you tense up it won't happen. This is a natural, easy process. Don't push or force, focus & guide.

When trying to ascertain if you have a true Mental or Astral project check to see if the contrary is true. If the scene you are in is one of a friend reading a book imagine him ironing or doing dishes. If the scene changes immediately to him doing dishes or ironing it not a true Mental or Astral projection.
If progress or success is occasional or uneven then check the list above and eliminate the cause of the problem.

Try these techniques every day or night for three months. Record all experiences, in detail, in a journal to study later. Stick to the schedule (three months), patients, practice & persistence are the key.

For further reading I would suggest;
"The Art & Practice of Astral Projection" by Ophiel
"Journeys out of the Body" by Robert A. Monroe AP etc.
"The Astral Projection Workbook" by J. H. Brennan good AP book with exercises.
"The Llewellyn Practical Guide to Astral Projection" by Melita Denning and Osborne Phillips ISBN 0-87542-181-4.
 
by Dan McClure
Freely distributable as long as the work is unaltered and author's name is kept with the article.