Mostly upploading this here to get hold of a high-res size... XD
Made a step-by step of an art trade piece I did for a trade with
As stated in the tut, it won't touch the fundamentals of light and color too much.... I recommend you to study the fundamentals in order to improve your coloring. This page has lots of nice free tutorials about digital painting. I learned a lot by reading James Gurney's book about light and color which i really recommend getting!
Nathan Fowkes has some really great tutorials and inspiration too on his blog. He's also conducting online courses (WHICH COST A LOT...OTL).