You can read ' Astral projection for beginners' by Edain McCoy, that really helped me to do it.
and ' Treatise on atral projection' by Robert Bruce, that is really a helpful and amazing book.
Theres a good CD I got from ebay called'Astral projection a 74 minute course' by Dick Sutphen.
There is a CD in the SoM online store which is really good called 'Mastering the art of astral projection' by Brad steiger.
Lady Snow is right,( she is an expert on astral projection), you need more than just one post to learn it, you really need to study and dedicate time and patience to learning astral projection.
It helps to practise regular meditation and chakra stimulation and cleansing.
Taking time to really learn astral projection is more than rewarding as theres nothing more liberating than leaving your body, it really is amazing, good luck