In this tutorial I go over how to add the subsurf modifier to an objects, and then how to control the shape of the object using your ability to set a "creaseThe Details The Bevel tool is a great way to add extra detail to the edges of a model – especially hard surface models In the real world, there are virtually no perfectly hard edgesEven a sheet of paper has some thickness to it, even if it is microscopic Using the Bevel tool to add even slight bevels to the edges of your models can be just enough for the edges to catch some extra lightInstead of letting Blender set sharp and smooth edges based on a fixed value, we can mark edges as sharp to have full control over what edges are sharp and not Just note that this requires an edge split modifier This modifier actually split the geometry making separate pieces
Bevelling Sharp Interior Corners Blender Stack Exchange
