So far, discounting those few times I’d felt hot, relaxed, annoyingly thirsty and tired, and then projected by accident from a half-asleep state while trying to get up out of bed to fetch a drink or take a leak, or momentarily had phased out of body to a consciously willed distant place of focus only to fall back into my physical form due to excitement; I’d only gone one other time consciously from a full waking state to that stage where you’re getting the infamous vibrations. As those almost painfully ripped through me, suddenly I felt as if I were separate from and yet just outside of my physical body, ahead of my chest, but though I could feel where everything in my room was somehow in fine detail, despite the fact that all was visually black around me. I couldn’t move much, and it sounded like a freight train was roaring right outside the room, too. After a moment, I couldn’t wake myself up despite the fright, either: like my body was unresponsive nearby, frozen behind me in dragon asana. In retrospect, I think I simply needed to will myself away at that point, and I’d have been out. Oh well.
If not for dumb luck or whatever, my actual successes have almost, but not always, happened while sleeping in the very same night after failed attempts. You can suddenly realize you’re dreaming, and will yourself out comparatively easily. I find that for me, I almost always momentarily return to my body (perhaps the truth is I’m seemingly waking somewhat; becoming aware of my physical form?), and then almost simultaneously to that sensation and awareness, I’ve either slid out the crown chakra a few times, or less so, popped out of the chest chakra. I hadn’t consciously chosen those locations to exit- I just willed myself “out” with intensity and focus. Anyway, this part usually, but not always happens just like vibrations will also usually but not always happen; being that after you feel a quick yet intense rush of physical arousal which comes on with said vibrations, subsiding together on actual exit, you are left in a state that can only be described simply as being, “more awake than when you’re awake”. I’ve never feel so alert, awake and alive. To put it another way, it’s as if you’re suddenly able to experience your reality as directly as possible instead of as usual; instead of reality being filtered through your sluggish, heavy physical body and senses. I guess this perception is why I’ve kind of personally decided it’s probably more like inward travel than actually going out of body. But I’ve learned from experience and confirmational sources that you can slam back into your body with your heart racing like a heart attack at any moment, or fall into a sleep induced dream-stupor. I’ve done both, and remember vividly the time I had swiped my hand through the fridge once, then twice to confirm, and realized I must be out of body again, then… BOOM. Speaking of which, in a different vein, a person can also, from experience, descend into the lower vibrational astral regions (maybe descending is just how my mind perceptually understands and displays something otherwise nonphysical), manifest astral weapons (particularly, though, if one were to practice this while awake instead of winging it, by using physical objects even like an umbrella to guide and stabilize thoughtforms), and for whatever reason if not simply for fun, there you can slay hordes of masses of astral wildlife which on arrival will try to glom onto you enthusiastically. 
It must be amazing to be able to project on command, and I hope some day to be able, myself.
cause again I’m not 100% sure if I ever been doing it correctly so I’m willing to talk to a spirit as my mentor and learn cause if I’m not doing it right then of course I’ll find out.