[alas,]

For my use so I can remember how to do this. d: You can use if you want, just be sure to tell me. ^^;

Step One : base color; color it down.
Step Two : more colors; do some highlights and shading, for example.
Step Three : blend all together. Do some smudging, too.
Step Four : once blending take black [or another neutral color] and select the line brush tool. Draw lines all over the coat.
Step Five : Do more blending and more smudging.
Step Six : Add more shading and highlights if wanted. :3