Sharyn has sent me a photo of a Yorkie and has asked for help in choosing the pastel pencil colours. For the silver grey tones I would use the cooler colours such as Cold Grey I (230 in the Faber-Castell Range), Cold Grey IV (233) and Payne’s Grey (181) with just a touch of 140 cobalt blue added if needed.
For the light areas this would be on a white base and for the darker tones the starting colour would be 233 then 181 and black (199) with a little 140 added if needed. There is also a hint of pink in the silver tones and here I would consider 132 (light flesh) first but you might need a stronger tone such as 131 (Medium flesh) or 189 (Cinnamon).
For the ochre tones I would start with Ivory (103) then add Burnt Ochre (187) or Terracotta (186) then strengthen this with Burnt Siena (283).
As I have said many times although it is ok to set out the pencil colours that you think will be needed it is always best to keep and open mind and discard or add more colours as you proceed once the base colours have been applied.