The most common problem people encounter in this part of the work is maintaining a consistent shape for their body. They find that even after long practice their head and arms will remain reasonably well-defined, but the rest of their imaginary body has a tendency to blur into amorphousness. This is a reflection of the relative density of nerves in the physical body. Eighty percent of our sensory and kinesthetic nerves are in the head and hands; half of the remainder are in the upper chest, shoulders and arms. Our perception of the rest of the body is substantially more vague, and depends as much on sight as on direct sensory connections. When one tries to build an astral body, the mind tends give each part of it a size proportional to the relative nerve densities.
This is really not so bad. You don’t need legs in the magickal space, since you are moving yourself around by your volition rather than by pushing yourself with muscles. You _do_ need arms and hands to do the gestures of magickal rituals, and lips and jaws to speak the words. If you find that after some practice you can’t maintain a full body image, don’t worry about it; just get by with what you do have, and imagine the rest of your body concealed by a robe or other loose garment.
The second problem people have is that their physical body twitches or moves when they try to move their magickal body. They unconsciously tense up the physical body, trying to “lock” it so that it won’t follow along with the magickal body. This is a matter of lifelong habit, of associating the sensations of movement with the volitional act of moving your muscles. One has to disassociate the sensations from the volition, and another simple exercise will help.
In your magickal space, imagine you are standing with your arms held out in front of you, palms facing downwards. Now imagine that you are turning them so that the palms face upwards, but that you are turning them _entirely with your eyes_. That is, you see them turning over, and feel the sensations of the changed position, but you don’t involve the part of your mind that moves the muscles. You should _see_ your arms move without willing them to move. (In fact, you are directing your will through your visual centers instead of your muscles, but it should not seem like you are willing it, at first.)
The first few times you do this, your physical arms are almost certain to tense up into rigidity. When you notice this happening, stop and do the relaxation exercises until your body is loose again, and then go back to trying to move your magickal hands again.
Once you succeed in turning your astral hands over without tensing your physical hands, you should try moving the fingers individually. Curl each one over onto the palm, and straighten it out again. Again, do the relaxation exercise whenever your physical body tenses up. When you succeed in moving the individual fingers without tensing up, try various coordinated movements: clenching your fists, grasping objects, karate chops, Vulcan greeting-gestures, and so on.
The hands are the hardest part of the magickal body to separate from the physical, because a major portion of our nervous systems go into controlling their movement. Once you have managed to dissociate movement of your magickal and physical hands, the rest of your body will be very easy, and can be done with similar exercises, if necessary.