The way you overlay your materials onto any model/object is critical to realism. The UV checker will allow you to look at the skin of an object more closely and allow you to align things properly.
In this section Dustin explains how UVs might need to be resized, relaxed, and/or stretched in order to make the texture that will be applied to flow properly and minimize artifacting.
Understanding UV islands, how they are packed in the UV editor and how packing will impact materials once applied to the model.
Dustin talks about understanding UV scale in the UV editor. Understanding scale in the UV manager will help make sure that the materials applied to the model later will match the texture of similar adjacent sections of the model. This provides consistency across the materials used in the final st...