Here is a very quick and shamefully rough process of how I approach painting a character within Photoshop.
All the layers used are normal layers except for a Colour Dodge Layer added at the tail end of the image and a Channel Mixer Layer which is set up at the beginning (this is set to monochromatic and therefore allows me to constantly check my image in a black and white state. This way I can constantly see my values clearly and easily) Oh yer, the pencil sketch layer is set to Multiply.
I normally work with just 2 or 3 layers, but I had no idea what colour to do this guy's clothing, so I put each piece on a fresh layer, just to make it easier to adjust.
(Original Coloured Pencil sketch)
(A Crummy Animation Of The Process)
(80% done)
(Finished: Womack The Nomad)
(any reference to my friend Paul Richards are totally coincidental :)