If one interprets Buddha's teaching superficially, one may assume - and some indeed do - that the world is fundamentally broken. The world is samsara, its nature is dukkha, our journey begins with primordial ignorance, the senses inevitably tempt us to hell, and the best we can do is stay cold and constantly on guard against our own flawed nature.
The more mature understanding paints another picture. In this interpretation, the world works a certain way, and in that sense its not broken, in fact we can say everything has its reasons and works due to its causes, resulting in every thing and even every person taking their places accordingly. From this standpoint the world is Perfect and works perfectly well according to its natural laws.
In the same vein, before the conceptual mind develops while building its subjective world and its notion of self or ego, there's indeed that great nondifferentiation. Rather than painting it in dark colors as "ignorance" we can see it for what it is - a blank slate! Starting from that blank slate there's a process of learning, driven by the mind's innate instinctual attraction to Peace. Yes, the childish mind's methods for seeking peace are very naïve - it clings to its pleasant experiences, resists change, fights enemies - but fundamentally it's driven by its instinctual desire to make things good.
From this standpoint, the ego is a process of seeking peace, or as Thanissaro Bhikkhu said, "our sense of self is an activity, a strategy for avoiding suffering, for maximizing happiness" -- it's just that its a childish and naïve phase of the larger Path ("Ultimately, though, self as a strategy can only go so far. This is where the not-self strategy comes in." - T.B.) The path into and through samsara is the beginning of the path to Nirvana, it is the path in the right direction - not away from it, even if it gets stuck in this childish phase for a few hundred billion lives - eventually it moves on and graduates.
Based on the above, we arrive at the Fundamental Goodness or Fundamental Sanity as a key Mahayana concept. To cultivate it in our lives means to be at peace with the larger picture, at peace with our past, our mistakes, our baby steps, our growing pains. It means to cultivate a deep confidence that at our core we want Peace, we want Goodness, and that our mind is fundamentally capable of figuring things out right, even though it takes time.
Ultimately, to cultivate one's fundamental goodness requires accepting the fact that the Buddha came from the same evolutionary background as we did, and therefore every one of us is a buddha in the making. Hence Buddha-Nature.
We are not wrong, we are not bad, we are just growing - that's the mantra.
"I may be confused or mistaken when it comes to particulars - and indeed I keep reviewing and adjusting my understanding all the time. I may have done some crazy things in the past, as part of my learning - but all of that was driven by my intent to do the best according to my state-of-the-art at the moment. I'm not an evil person I swear my intentions are pure - but I am not perfect, I'm only learning, and I will keep at it." - that's how.
And of course the physical practice of moving around gracefully, keeping good posture, sitting down slowly, mindfulness of the body.