The goal is (that's what I do anyway) to slowly build down activity in your mind. Remember that 'staying concious' doesn't mean you should be able to name 20 digits of Pi at any time during your practice (

).
If you try to hard to stay concious it usually doesn't work for me, the only thing you have to watch out for, is that you do not lose track of what your doing. Don't get too distracted by the sensations, dont fall into your hypnogagic images (you might fall asleep) and don't forget that you are trying astral projection.
Especially in the beginning, I would look back at my session, and noticed I had just lay on the bed not doing anything, I completely forgot I was attempting astral projection.
Also, don't wait for the vibrations, if you keep anticipating them, you will get too excited. In the ideal situation, you lay down with completely relaxed muscles, your only intent is to project and the only thing on your mind is your technique.
Try to work towards it one step at a time, until the step becomes natural to you, then take the next. Also the most importing thing to remember for me was, that trying too hard negates the relaxation, and trying to learn too many things at the same time negates the 'the only thing on your mind part'
