Practice deep, controlled breathing. Think about your body from your toes to the tips of your fingers & deliberately relax each part of your body as you work up. Try this combined with sensory deprivation (ie eye patches & ear-plugs) if the deep breathing doesnt work.
A guru of meditation (I think I read this in E for Ecstacy or one of the other Saunders books) described ecstacy & it's related compounds as a "short-cut" to Nirvana. To a degree I support this concept... But I think people who are able to trip themselves out have ultimately more satisfying, sprirtual trips on psychedelics & entactogens. In other words, if one is able to successfully meditate into a trance, one is already closer to that point before any chemical is introduced.
I've had numerous out-of-body experiences & some of them have been either due to exhaustion, illness or due to meditation. Some even from zoning out watching TV. I am into my 40's & although I've been able to meditate successfully since my 20's it's only recently that I've reached states where I am totally unaware of my body, without much effort.
Training & time is what it takes. Start with the deep breathing, really get into it & take your time, deepening your breaths & increasing the space between breathing... If you find yourself in even a slightly relaxed state, you're moving in the right direction. You can ratchet the experience up with decreased sensory input but this wont really work on it's own, you gotta try the breathing first & once you've got the hang of that, add in the eye-pads ear-plugs.
Well mixed, long, trancey dance music mixes over headphones, in a dark room are equally effective but obviously the music will draw your attention & alter the direction of your travels. But it IS a good way to start
E n j o y !