Much of what we consider as spiritual progression is about diminishing the ego, letting go of the sense of being a separate self and realising Oneness. It starts with recognising that we are not this body, we are not the apparently limited human form. We recognise that there are no real limits to the body anyway. We couldn't really say where this body ends and the environment begins, because the body is a flowing part of the environment. The vague sense of identity we have attached to the body is flawed. Our real spiritual nature is formless and limitless.
It stands to reason that the less selfish our identity becomes, the less material, the less limited and the more spiritual we seem to become. It's not really that we become more spiritual. Rather it is that as the mental association of being a limited physical being is reduced, the natural free spiritual nature shines through. It's like removing layers that seem to cover and limit our true being. This usually happens gradually. As the strength and hold of the selfish ego is reduced, the more the true free nature of being is revealed. It's a simple peace and contentment that is always here but seemingly hidden.
So let's look at some techniques for reducing the ego, cutting down that sense of being a separate, limited self. It's worth noting that although we're discussing the ego here, it's not a real thing. It's not a real entity, only a thought-based presumed identity, that seems to have a monopoly on human life.
The aim is to let go of selfishness. That means letting go of belongings. Belongings bolster the sense of being a separate self; but ownership isn't real. Nothing belongs to anyone. Let go of the sense of ownership. Nobody owns anything. Let this understanding permeate through. There are no separate things, no separate beings, and no ownership of things. It doesn't mean you have to give things away. Just let go of the attachment to objects or others. It doesn't mean you have to turn your back on people. Just let them be as they are. It allows a greater openness and freedom to flow.
Recognise how drama and emotional turmoil rock around the ego. Let it go. Let go of the drama of life - reactions and retaliations, gossip and accusations, blaming and complaining. The ego loves getting caught up in it all. It strengthens the ego's sense of being separate and different. Let it go. Let the drama play on without getting caught up in it. It's not who you are. You are witnessing the world's play; you're not a character in it.
Accept life as it is. It's not that life deals you a hand and you have to accept it. You are Life. The Whole of Life is played out through the seemingly many separate perspectives. All perspectives are the One Life. It will play out how it plays out. Resistance to life just builds up walls of limitation. Let those walls come down. Let life just flow as it is, and know that you are not one who flows with it or is rocked about by it. You are the ever-present Stillness in which the flowing is perceived. That doesn't mean allowing illness to go unchecked when there are doctors who can help. It doesn't mean leaving someone to suffer if they have fallen. It is more like accepting what appears to happen and allowing the natural responses to life's events without objecting and complaining. If work needs to be done, accept it. If something fails to happen, accept it. Accept the flow of life.
Help others. Now, there really are no others. There is only One Infinite Being appearing to divide itself into many. But helping 'others' naturally breaks down the mental barriers that the human mind has built up. It breaks down the barriers that seem to divide, thus weakening the hold of the selfish ego. The most selfish ego doesn't want to help others; it would sooner fight them. The least selfish ego will put others first and look to help them. So this is what we should do if we wish to weaken the hold of the ego. But it should be understood that there really are no others. What happens when 'others' are helped is that the oneness of love comes through, breaking down the barriers of division.
There will come a time when the ego is released and is seen to be nothing other than a dream of separation and identity, an imagined persona that has disappeared. The reality is One. The Whole of Life is One.