Once the eyes were right I began to develop this portrait by laying out in the lightest colours, the shape of the face.
Doing this lets me see the shape the face needs to take as well as allowing me to begin to build up the layers of colour. The slower I work the better the result. Pale layers first then gradually getting darker whilst paying attention to the colours I can see in the fur. Darkest darks and lightest lights are important to lay in.
I also build up the fur slowly and again by starting light and moving towards dark.
Being careful to pick out the colours that make up the White fur is very important as this again helps to give depth. By laying in the short fur first then moving towards the longer fur I can adjust the shape as I go until the portrait is complete.