My standard way of beginning any animal portrait is with the eyes and nose. If the eyes don't read correctly, the whole painting will fail, so it is good to do them first in order to quickly know if you will need to start over.  Painting the nose gives me an immediate sense of the darkest tones I will use.  This makes it much easier to determine all of the tones to come in the painting.

Next, I paint in some more of the darkest tones under the ears, again to give me a better sense of the how dark or light the tones around them will be.  I then paint general, wet-in-wet washes to loosely define the areas of warm and cool color regions.  This isn't about tone with these washes; it is merely to build a very basic map of "zones" to start organizing things in my brain.

Now comes a very unique stage (unique in that I've never seen another artist use this technique).  I call it "texture washes".  Basically, I just paint little "dashes" representing fur over the entire dog.  I make sure that the fur marks are going in the proper directions.  I also darken just a few obvious contour areas along the way (ex. on the right side of the left eye), but only very obvious ones.  The main idea here is to create fur texture. 

This is a close-up of the previous stage so you can better see the textural marks. Applying this technique is not how most artists paint short fur.  Most artists wait until much later, often even toward the final layers and usually done several times in several layers.  For me, it is much easier and more natural looking to do it like I've done here.  With this method, you simply cover the entire animal now, and then you just paint the rest of the animal with washes and layers that deepen tones and establish form.  There is no other application of fur texture, except in very, very small areas and only very occasionally.  The subsequent layers placed over the top of these fur marks do an amazing job of softening the marks, while allowing the textural effect to still show.  The end result is a very realistic effect of short fur.

With the fur texture established, now I simply begin to lay glazes with faded edges to establish the contours more accurately.

The same process continues, defining smaller and smaller contour areas.  Once I think a new level of precision is reached defining these contours, I lay in a wash over the whole dog to darken everything, keeping the relative tones the same.  Then I re-evaluate, define more contours, and darken the whole dog.  This process is repeated again and again.

Along the way during all of these layers, I adjust relative tones where needed.  For example, in this picture, notice that the darker areas to the left of the nose, just above the upper-left of the nose, and the "jowl shadow" to the lower right of the nose are slightly darker than the previous picture.

Again, the relative tones are adjusted, and then the entire dog is darkened.  Notice here that the whole dog is darker, but in addition, certain smaller areas are darker to adjust relative tones.  For example, the lower left of the dog, near the shoulder is relative darker than it was in the previous picture.  

Also, in this stage I began to render the lips/gums more.  Note that the lips/gums look very strange at this point.  This is typical of mouth areas in dogs; they often looke very strange until near the very end, usually after glazes are applied to unify all the abstract shapes.

The same process is continued on the main body of the dog until the final tones and contours are achieved.  The mouth and lips/gums are rendered more with very small contour shading.  Then a shadow glaze is applied to the tongue, and one or two pale unifying glazes applied to the lips.  Then the dog is complete.  Notice that no other fur texture was painted except for that very early application.  Notice how the fur texture is there, but it is very subtle, just like a real dog would look!