Cutting Seams for 3d models

 I'm a bit of a novice when it comes to UV unwrapping and setting textures to my 3d models. I get my model in Blender, and I hit Smart UV Unwrap, and instant regret. I see dozens of little islands, basicalyl the whole of the UV mesh all scattered around with NO feasible workaround to create multiple variations of teture for my 3d model, there's no reusability that way. 

Luckily, our AgileGameDev on Youtube came up with a unique tutorial on how to create seams, those things that ensure that islands are set in a certain way as to allow a more seamless (pardon the pun) way to create your UV maps for texturing or texture painting.

Hopefully this helps!