In his attempt to further illuminate the meaning of wuwei (non-action) — no easy task to be sure — Alan Fox ("Reflex and Reflectivity: Wuwei in the Zhuangzi"; Hiding the World in the World) refers us to that most simple yet profound metaphor: "The forgetting of the foot means the shoe fits comfortably." (Zhuangzi, 19; Ziporyn) "Therefore the most effective mode of human experience is to blend or 'fit' (shi) into our surroundings in such a way as to allow ourselves to respond effortlessly and spontaneously to any situation or circumstance, which is simultaneously affected by our presence within it."
All metaphors break down at some point and this one seems to do so immediately while still delivering us where it would have us go. What it does not do is demonstrate the reciprocal relationship between the foot and the shoe. If "forgetting the foot" is a positive value (and for the moment we will assume that it is), then one might believe that all we need do is find the shoe that fits. (Become a hermit in the woods; achieve the most comfortable life possible.) But the real punch in the passage in which this metaphor appears is the suggestion that any shoe can be made to fit. The simple fact is, we will never find shoes, circumstances, that will not in some way pinch us if we allow them to do so. It is we who interface with the world of circumstances who ultimately determine whether we and they comfortably "fit". And this we do through the practice of wuwei.
Wuwei — let's call it 'doing nothing' — is allowing (making) circumstances to fit. Wuwei, then, is a kind of adaptive response to the world in which we find ourselves. Nothing can get at us because we allow every circumstance to fit. It is we who make it so. "Doing nothing", then, is doing the hardest thing of all.
But Fox takes it a step further: A circumstance is "simultaneously affected by our presence within it." Our attitude toward a situation transforms that situation. The relationship is reciprocal. Not only does the foot adapt to the shoe, but the shoe is thereby adapted to the foot. When an event that might have been construed as 'harmful' is met with an attitude that renders it "beneficial", that event is effectively transformed. The practice of wuwei is thus not at all a passive exercise, but a most active and engaged one. It transforms not only the practitioner, but also the whole world.
You can check out Scott's writings on Zhuangzi here.