Attached are some more steps in the process. Keep in mind I'm not a paid professional - yet! - so my steps aren't necessarily the right way but what I felt comfortable with and still gave me a sense of organized process. In the first image, I painted out the fur, varying from high- to low-tones and not focussing on any specific one. This step put most of the image together with lots of room for refinement. For example, I noticed that the dog's face seemed a little too long so I made some adjustments that better resembled the subject. Although I didn't have a photo of the dog in the pose that you see, I used other photo references to help me place him in a similar manner. One thing I had to be careful about using references in this way is that I started taking different little bits from each photo for the dog and each photo wasn't specific to the dog but just an example of a similar breed.
In the second image, I focused on making the image more like the dog in question. At this point, the only photos I would refer to were of the dog though the poses were different than the one I was painting. I was able to focus on the more specific details about this dog and apply them to this image. Having too many references - especially disparate - can be confusing and distracting. I also took the time to make the fur more realistic. That is, I downplayed each hair and tried to make them less distinct individually and make them more distinct as a group. When we see an animal's fur in life, we don't notice each strand but rather clumps as they're arranged around their body.
In the third image, I started to block in the background. This image needs to be done by Valentine's Day so I had better get back to it!