Visualizing the Expansion of the Universe

Question:

I have difficulty understanding the expansion of the universe. I have seen it explained as the expansion of ‘space itself’, as if remote galaxies are not in fact accelerating, but the gaps between them change in their nature, giving only an impression of increasing distance. I have also seen it explained as galaxies being ‘carried along’ with the expansion, as if no accelerating force were required, but they were indeed accelerating. I’ve read the expanding bun loaf explanation, which suggests a real and increasing displacement, caused by forces acting outwardly upon all matter. The forces required to accelerate a galaxy cluster would, of course, be remarkably high and it’s difficult to imagine their source or how they are applied to galaxies in order to make them move. All of them seem odd! Could you perhaps help me to visualize the phenomenon of expansion more clearly? I would especially like to know whether the movement is a real change in distance or only an apparent one. For example, if it were possible to install a long rigid ruler between two receding galaxies (both with negligible local movements), would the ruler confirm the same expansion movement as our current astronomical measurements yield? Or would it show no real movement? Thank you.