Source materials are made up of two files:
A VTF (Valve Texture Format) file that actually contains the image of how the VTF is rendered in-game
A VMT (Valve Material Type) text-based file that defines the material type
You can have multiple VMT files that reference the same VTF file. So, you can have multiple materials that use the same image differently.
The .bin folder contains the program you need to create your own materials. All you need is an image editor capable of creating targa (.tga) files and a proper folder structure.
First, let's set up our folders. For vtex.exe, the texture-creating program, to function properly, you need to create two folders: one to hold the texture source files and another to hold the compiled materials. The first folder we need to create in your mod folder will hold all the TGA files. In this example, the mytextures folder will contain all of our textures. Create the following folders in your Steam folder as follows:
steamapps\common...