Skin colours - I always tend to stick with 'skin white' as the base colour, although with this pic I was working on cartridge paper (the original sketch in my visual diary), which carries the markers differently to the paper I usually work on. The 'skin white' came out much more orange on the cartridge paper I found and needed lots of toning down.
'Dull Ivory' is one of my favourites for darker skin shadows, and the bluish tones were a 'wash' of 'Pale Lavender' or 'Mauve Shadow'. Can't remember which. :~P
Other colours used - 'Clay, Blush, Barely Beige, Buttercup Yellow', and 'Caramel' was what I used for Ron's hair. And of course my favourite marker, which is the Colourless Blender.
As for the fineness of Ron's hair, it's mostly Copic. The only photoshopping in his hair was the highlights - the 'white' strands of hair. The pic was A5 (5.5"x8").
Hope that's a help? :~D