You could look at what the Japanese call "No Mind" or Knowing Mind as a non-judgemental or non-limiting state of mind.
You could also think of it as a Non-Thinking state of mind.
Instead of worrying or thinking about what you are doing you just get on with doing it.
This isn't to say that you don't care. Nor is it a simple flailing around while you are doing what you are doing. It is practice with a point or a purpose.
It is practicing while knowing what you are trying to do.
When dealing with "complex systems", to know, it helps if have a modicum of understanding.
At this point it might be helpful to talk about consciousness.
You could model consciousness as the "control center" that is at the center of our being. It is what controls both our mind and our body and it is the part of ourselves that can watch ourselves thinking and doing.
Another way you can think about consciousness is that it coordinates and/or unifies the things that it connects.
The idea of talking about consciousness and modelling it is so that you have a way of understanding what it means to be in a state of no mind or knowing mind.
Towards this end we can model consciousness as having two main states, it can be expanded across time, and it can expand across space.
These two states can affect the way that we use our brain.
When our consciousness is expanded across space then it puts our brain into thinking mode.
This can be useful when we are trying to figure things out or understand things.
It can also be used for looking back at experiences that we've had and perhaps can be used to look forwards towards experiences we'd like to have.
Experiences are times when our consciousness is expanded across space.
In this state of being our brain is more likely to be processing sensory inputs from both the world around us and from inside of our body. It can also be responding, or sending out signals to our body in response to what we are doing.
And so you could call this the "Doing" mode of consciousness.
One important aspect to understand about this way of modelling consciousness is that consciousness is limited. We each only have so much, and so the more we are in the state of thinking the less consciousness we have to focus on what we are doing and vice versa.
The upshot of this is if you are thinking by focusing on a problem that is in your head, or if you are using thought to understand something, then you might be better of doing nothing, or at least not doing something that requires a lot of awareness.
On the other hand, if you want to do something with skill and awareness, then the less you are in the state of "thinking" the more consciousness you have to spend on using your senses and doing.
Simply understanding that consciousness is limited in this way can be a good reason to become aware of when you are thinking and when you aren't. It also means that you can practice choosing which state you want to be in.
Want to think less? Then focus on using your senses.
See what is around you now. Or focus on feeling your body. Or focus on feeling your body while you use it.
Or simply turn your mind off.
To think less, direct your consciousness outwards into the space around you, or into the space that is in your body. Notice what is around you or within you. Use your senses, and if you like respond to what you sense.
And if you want to think usefully, then focus on what you are trying to do or on what you want to create, or on things or moments in life that bring you joy and make you smile.
Or if you really want to, you can focus on the things that upset you.
The idea is that by being aware, whether you are thinking or doing, you can choose the way you act or think, and the way you respond.
Limiting consciousness in this way seems a little bit like a bum deal.
Is there no way we can expand our consciousness, do more with it?
Yes there is. The notion here is that the things that we do, or create, the things in the world around us, these are all units of consciousness called Ideas.
More saliently, the things you do can be called ideas.
Say you want to learn how to touch type. That is an idea. Ideally, you practice to the point so that you can use a keyboard without having to look, even without having to think. When you train for long enough, you make the knowledge or understanding of using a keyboard a part of you. In this way you don't have to think. In this way, when you are typing, you don't have to think about where the letters are, you can instead focus on what you are trying to write.
It is as if the idea of typing has become a part of you. Instead of you doing the typing, a small program, a small idea, itself a unit of consciousness resides inside of you, able to help you type whenever you are at a keyboard.
Language is another idea that you can think of as a (rather large) unit of consciousness or idea.
There are times when perhaps you do have to think about the words you use, perhaps when in a sensitive business negotiation, or when teaching or training relatively in-experienced people or people with different learning styles. But on a day to day basis, you don't have to think about how to use your mother tongue. Instead, like when typing, you can focus on the idea of what you want to say, and the idea that is the language that you speak, turns that idea into words that your mouth delivers.
All that is required, when typing or speaking, is that you know or have a clear idea of what you are trying to say.
So you can reach a partial state of no-mind, or knowing mind, by learning skills like typing or speaking. You then have more consciousness to devote to thinking about what you are trying to say or do.
But that's not really no mind is it? Because you are still thinking, even if it isn't "how to type" that you are thinking about.
Going back to the idea of limited consciousness, or "finite amounts of consciousness", the thing that limits consciousness is space and time.
We can expand our consciousness across time while thinking. Or we can expand into space while doing but, with the aforementioned consequences, the more we go in one direction the less we are in another.
What if we expand into space completely. What if we completely immerse ourselves in what we are doing. Do we then leave the realm of time completely? Does our consciousness then become unbound? Unlimited? If so, what does that mean?
Lets pretend or assume that space and time is like scaffolding around a building, put there so that it is easier to construct the building. A better analogy might be training wheels on a bike. Training wheels ideally give us the chance to get used to steering and using the pedals and brakes. Now imagine training wheels that you could gradually raise, so that you get more and more freedom to lean the bike. Eventually you take the training wheels of. You are no longer limited by them. You are to a larger extent, free.
You could look at time and space as a set of training wheels that help us get used to experiencing this world. Expand into time or space completely and we become free of those limits.
You become infinite. Unlimited.
Getting back to what we can sense, if we manage to expand our consciousness completely in space, what could it mean?
Well, no thinking for a start. No mind!
But if you expand into space with the idea of doing something in particular, creating art, riding a motorcycle really fast, doing a yoga asana, then by expanding completely into space you can focus on using your senses to achieve that idea.
Because time is no longer a limiting factor you may find that you can sense change, information or energy as it is happening. And that you can respond as it is happening.
Just because you are not thinking doesn't mean you don't know what you are doing. You do. However, instead of thinking about what to do, you just get on with doing it. Or you watch yourself do it. You become the audience of yourself.