Hmmmm...
I do concur with Vovin and the rest of you here, and would even go further to say that all psychotropics, psychedelics, entheogens, dissociatives and the like should be viewed with immense respect for their ability to shatter your reality. In fact, I think many people should probably not do them at all. Of the people who can benefit from them, a majority probably should have a "coming of age" ceremony or three, and then forget about these realms for a long while.
The fact is, that not everyone is cut from the shamanic cloth. Even the most psychedelic tribes I have encountered never put more than a handful of people on the path to shaman-hood.
That said, there are enough of us around on this globe who are drawn to this. Furthermore, it IS possible to gain some degree of mastery in these hyperspace sojurns. There are treasures to be found and they can be brought back.
In this way, entheogens are rather like any other extreme activity... skydiving, underwater scuba salvage, hang gliding, or racing motorbikes. Like these activities, there is only so much you can learn by academic research. You learn to fly a fighter jet by doing it... first with guides and teachers of course, but eventually by pushing the envelope a bit each time you go up.
The common thread that runs through the posts here seems to involve preperation for the experience and digestion of those experiences through purely academic and intellectual means. I submit that no amount of reading or thinking will accomplish either goal. But there are things you can do that do work.
Again, as with most extreme sports, you must have good equipment in good repair... and you should check it intensely before every voyage. You don't jump off a cliff or go cave diving without 100% confidence in your equipment, do you? Well with psychedelics, your equipment is your mind. Of course your chosen substances are part of the puzzle and should be immaculate and measured, but in the end, your mind is your vehicle here, and it should be in good shape BEFORE you take off.
You don't go racing downhill mountain biking without well serviced brakes, but yet many people dive into hyperspace without even the slightest thought as to the shape their consciousness is in.
This is getting a bit long, so I will simply sum it up by saying that if you do psychedelics and don't meditate, practice some form of contemplation, dreamwork, internal yoga, and some spiritual code by which you actively strive to be a good person... you are asking for trouble. If you have fear, anger or other negative emotional issues, they WILL come up and bite you in the ass at some point. Do your best to deal with these things while sober, and don't be in any hurry to fly to the moon... let alone a 7th dimensional moon of an astral world.
Another good rule of thumb is to not journey again until you have digested and processed what you learned or were shown on your previous journeys. This, again, is not an abstract intellectual exercise, but should be accompanied by real action on your part. Change your life, stop lying, be better to people, channel what you receive through art, music, words or dance... go hiking, go surfing... whatever. Don't think you can just sit on the sofa taking changa rips and playing video games. You will have your ass handed to you in a guilded tesseract.
Be well my friends.
HF