I've been astral traveling for many years-- the first time was a complete surprise! Like most frequent travelers, I can't always do it when I want
to: sometimes it works, sometimes I just get a nice nap
My humble advice is the same advice given to me so many years ago. You are trying too hard. I know, it sounds like the most horrible advice ever. How
can I achieve it if I don't try?
I read and read and read, tried every single technique I could find, downloaded all sorts of songs and sounds, and nothing happened. So I made my own
technique that was a little bit of the other techniques I had tried. I trashed the bits that didn't work for me, kept the bits that seemed right, and
added a few of my own methods. This new moshposh method works for me.
Perhaps, the next time you attempt to leave your body, go into it with a lackadaisical attitude. "I hope to leave my body, but if I don't that is ok
too." The base key is to be relaxed, so this "I don't care" attitude will help with that.
And don't beat yourself up if you fall asleep. Some of the best experiences comes when your body is sound asleep! And embrace any differences: some
people see a silver cord when they are out of body, some people always feel the vibrations and/or sinking feeling, and some people don't. There is no
right or wrong way. I, for one, have never seen the cord, and if I'm feeling the vibrations then I know I probably won't get out. That is just the
way it works for me.
I think the biggest thing is to be laid back about it. Sometimes your trips will be long, sometimes short. No big deal either way. Sometimes you
excited yourself/scare yourself back into your body. Ah well, next time it will be longer.
If you can find a group of people to travel with then all the better. I belong to an online group and we've made plenty of trips together. This can
be weird at times, but educational. Just pick a place, like Stonehenge, and focus on that before you meditate (or whatever your method is).
Again, there is no right or wrong- just whatever works for you. And if nothing works for you yet, just relax and allow it to happen. And it will.