What does [the feedback] 'RSI layering of shapes' mean?

Layering of shapes means that the surface is not constituted by a continuous layer, like, for example, the canopy of your computer is, but is actually made of literally layers, like an onion, that are cut with different shapes, every shape cull on each other, and there is what we call echoing. Try to use a few established angles, use this one and overlap them to create nice dynamic shapes.