""Warning"" This technique can be very uncomfortable, scary to some, disorienting, can cause major sleep paralysis, and almost always put the practitioner in the astral with out them even realizing it...but I have found that it is also very effective for beginners.
I came up with this Technique after I was in a car crash where I hurt my neck and back pretty bad. I was having problems meditating on my back so I needed a Technique that would work with me laying on my side and stomach and this worked very well.
Lay down to sleep in any position you want. Lay perfectly STILL...don't move a muscle! In your mind say "red light my body is not allowed to move." Repeat this over and over until it is burned into your mind. Now let yourself fall asleep (not moving...if you do feel a need to move you must say in your head "green light" move to your new position; lay perfectly still again and say "red light".)
All this sounds silly, but what you are doing is telling your body not to move when you fall asleep. Now trust me you will want to move and roll over in your sleep...but if this Technique is done correctly and commanded with force! You will find that it is not your psychical body moving and turning during the night...but your astral body. Just catch yourself doing it and Boom! you are astral traveling!