How would you go about obtaining trance states of consciousness?

try a book on astral projection..

Try holding your breath for a really long time. Let me know how it works out for you.

I use Qi Gong. I can achieve them all relatively easily these days.

check out this site
http://www.spellsandmagic.com/

I discovered this way myself, I watch the clouds especially when they are moving fast don’t think of anything or try to find shapes, just watch them, clear your mind and relax

Not a hobby for beginners! But you’ll find it in detail in the following book. Good luck!
Blessed Be…