The most fundamental idea in shamanism- to explain it to someone with a background in Western-style thinking, it would sound very differently to explain to someone indigenous because those things that go without saying vary so much around the world- is that consciousness is more fundamental than time and space.
We are not living in a physical world, and then consciousness erupts fully armed from someone's forehead (to quote a Western legend). We are blobs of consciousness, dreaming of a physical world, together.
Yeah. Groovy, isn't it?
I remember very well the first time I grasped this I spent hours staring at my feet running up the hill towards my university yelling to myself in my mind (I hope it was in my mind) "It looks so real! It looks so real! It looks so real!"
Now the kicker is that, once you've gotten over your initial reaction (provided it came as a surprise), it doesn't change that much. The dream is still there. You interact with your dream as your dream character the same way as you used to interact with your perceived real world as a perceived real character. Your dream still works the same way- it is still good to pay your dream bills and interact with your dream government departments at the dream appropriate times to avoid dream trouble.
You can still describe your dream world using dream mathematics to make certain dream predictions and use dream tools to build other dream tools to do certain things you couldn't to before, which results in having stuff in your dream like electric cars and the Internet.
If you want to dream-fly, it's still a really good idea try to lift off while standing on a level surface rather than after having jumped off a dangerously high area, in case you need more than one attempt. Because it is still possible to take a dream exit by using very familiar mechanisms for transforming your body into something the dream rules say will now blend into the environment.
But why on earth does everything just stay the same? Wouldn't you think that when you figure out you're really consciousness, that the curtains would fall and you'd get a prize and that'd be that? Well, not exactly.
You see, we as consciousness, we took upon ourselves on purpose to focus in such a way as though we were having a, well, realistic physical experience. It was all very intricate and very well thought out and lovingly set up. And being here does involve a certain amount of choice that happened before we arrived- the stuff we can't really change right now- but it also involves a huge amount of stuff that we absolutely can change. But not matter which, it's still us doing it- the slow-to-change stuff is simply set up that way in order to keep the experience together. And it just happens to be more important, to us, to keep the experience together, than to be able to fly instantly on a whim, changing the rules of gravity (I haven't seen it done without tools, personally, but I'm pretty sure it can be done).
There is a mechanism that was invented in order to have this experience world where we could experience this mixture between structure and freedom. It's called thought.
Because thought really is less fundamental than consciousness. Consciousness is just there. I think "clear-headed" is the usual mundane term for describing it, it happens when you relax your thinking process and let yourself just experience your surroundings. Thoughts clear up, and consciousness is left. It's really adorable and playful, but also very smart and wise. Lots of people call it God- or Christ consciousness, or spirit. I like to just call it consciousness. Fewer thoughts involved in the description that would need sorting out.
Thoughts are a limiting mechanism on consciousness. They are not really built in to who we are, but they are build into the style of dream we are having, the reality we are focusing on experiencing, they are a self-imposed limitation we can experience in order to know what it's like to be something, and not something else, because that's kind of hard as a blob of consciousness. Individuality can get a little blurry when you're a blob among blobs.
There are big thoughts and little thoughts (I just made that up, but I hope it will get a point across). Big thoughts are the kind that we did before we emerged from our mother's wombs- that we will have a body, that's a thought. That it will be of a certain tribe here on a certain planet where there are certain rules of physics that operate, that's a big thought. A certain era, certain predispositions, maybe even some way-points and important events and important friends. That's all predetermined. Not by other people. By us! And if you really really wanted to, you can even change the big thoughts- it just so happens the easiest way to do that is to go right back to the drawing board and set up a different life. And the simplest way to do that is usually not to practice flying on the way down from the Eiffel tower, but to live it out, and then try something different. You have all eternity, what are 80 years give or take?
This is where the small thoughts come in. Once you're more or less settled that you're okay with being in a certain body at a certain time and having had certain key experiences, then you're free to roam, so to speak. By chosing your everyday thoughts, you can completely direct your life, within the more rough limits that your big thoughts set for you.
Now what you need to know to do that is that our reality, our dream, is so designed that when you've done your thought-choosing and the reality starts accommodating itself to those thoughts, you get the experience, and that experience feels real. That's why there are so many arguments. Everyone thinks that obviously their point of view is correct, they just experienced the living daylight out of their truth. And they literally did. It was real- for them. Just as your experience is real to do. This is helpful to keep in mind when dealing with other thinking beings.
Now, the main issue we may have with our dreaming that isn't straight forward is that we've been thinking and experiencing for a long time without really knowing what we were doing, which built up a lot of momentum- a lot of little thoughts that sort of became like big thoughts in that it's not really obvious how to change them. Now keep in mind that even big thoughts can be changed, and even without living out your life and starting again if it's important enough, so most certainly these accumulated little thoughts can be changed. But because our experience seems so real, it's not so obvious how, because of the momentum and the reality of the experience.
This type of sticky changable thought is commonly known as a belief. It's still just a thought, nothing sacred about it, can be changed- but doing that might have a lot of implications because in our cultural evolution over space time we invented a lot of intricate little networks of beliefs and ideas that depend on each other that all have momentum, so it's really helpful to figure out what those are. We can still use them- especially when interacting with those who aren't aware that this is a dream, it might be the only way- but we don't have to totally believe them.
That's it right there, the last sentence- the essence of shamanism. We play the game, but we know it's a game with a certain part of ourselves, even while we fully experience and embrace the realism of the experience even knowing that others take it seriously.
This idea contains all the traditional traits associated with shamanism- the trickster, because we know it's a game and we can adapt our behavior to other people's beliefs and being mindful of the beliefs we're using ourselves- the shapeshifter, because we can be flexible with the beliefs we are using, and move in and out of them- the healer, because we can help others chose better beliefs, even if they don't know that's what we did- the adventurer, because we can pick a quest and savor it- and the wise person, because, let's face it, if you know about the fundamental nature of reality, you tend to give really good advice. Until you don't, sometimes, but then you do get better at dealing with that as well. And the visitor of other worlds, because even if the big thoughts remain in place, you can use a change of belief to experience tastes of other worlds even while primarily still focused here, which can be useful and exciting for all sorts of purposes.
Specifically, the playing of the game takes the form of focusing and releasing.
Focusing, because that is the same as choosing a thought, either by looking at something already in the world or something you make up in your imagination (which is really just part of you that stayed a flexible blob of consciousness). So to play the game differently, you observe less, and you imagine more- take your attention off the already-existing world (except to the extent required to handle things) and imagine the heck out of yourself, and repeat the good parts until that's how you experience yourself. It works best when by the time observational reality catches up with your imagining, you may have forgotten you wanted the change in the first place, because the imagination becomes more important. If this sounds like daydreaming to you, it is. It's just that the idea that consciousness comes first and physicality second allows us to discard the idea that daydreaming is not useful. As far as I can tell, it's the most useful activity available to humans bar none.
Releasing, because you have already focused on many things without consciously intending to, and many of those will not be particularly enjoyable, so they tend to crystallize- if you just keep thinking the thought exactly like you did for a long time, you tend not to feel it as much. This is commonly referred to as the comfort zone. The advantage is that the haphazard thought is so close that you don't really notice it. The disadvantage is that it's still active, still shaping your reality. Commonly, you would blame people or circumstances in this situation, but shamanically, you can place blame on a thought- network of thoughts, way of thinking- that you may be unaware of. This is good because it lets everyone else off the hook, and it's also good because it allows you to do something about it, and you can also let yourself off the hook because you weren't aware what you were doing when you set up your thoughts in the way you did. If you're fine with your general direction, you don't necessarily need to do a lot of releasing, but once you start focusing, you may notice certain turbulence-like experiences. Just accepting it as natural and riding it out and not being too worried by it (and not letting it persuade you to return your focus back to the familiar but keep it on whatever new idea caused the turbulence in the first place) will be enough, lots of times. If it's not, you can give the turbulence a little special attention. Focusing on it will amplify it a little bit, but it will also help to recognize it's not all that real by turning it into a caricature. This is commonly known as courage, going forward in spite of fear. It will help you ride it out faster. Finally, you can assume the thought that caused the turbulence, and change it into something nice- its polar opposite will probably be really nice if you can figure it out, but anything you think you would like will do.
That's it. The rest is tools and techniques and ideas and theory and adventures you can have with all of this, but it's all just a spin on these ideas, various kinds of it.
I hope very much that this information clears some things up for you.