The most important thing to know going-in is that you have to have an anchor; HAVE TO. And it's critical that you have it established BEFOREHAND. It should not be anything complicated or convoluted, it can't be. It must be deeply personal, because once you're undertaken in this it WILL be your sole tether to the Real. In the wilderness of mirrors you must, must, test everything, absolutely everything you encounter against your anchor; your proofing-stone. It is not unlike the forge of Hephaestus, it can not be. The anchor must be your great anvil, and you Tubal-Cain: the first worker of metals, the original Crafts-man; he who was the great artificer, who proved the strength (which is the quality) of plowshare and sword alike against his black-iron anvil; it is the black cube of Saturn, it is the black cube which was throne of every pharaoh, the monolith of 2001, the Kabba stone of Mecca. For you it must, MUST be the stone that holds that sword which is Excalibur. If not.....then it will be nothing less than the carbonite slab in which Han Solo was himself imprisoned in. And what specifically was the effect that carbonite imprisonment had on Han Solo? If you recall, it was blindness...