Here's the finished dog sketch. I've used the eraser to soften a few marks before going back over them for a more even, hatched effect in places, particularly the shadowed side of the face. The 'hairy' look is because I've used long, coarse marks. If you're drawing a short-hair dog, and have time, keep your pencil sharp and use finer, shorter marks, keeping them close together. You can also use more even shading (using the side of the pencil if you wish) before you add the hair texture. The more carefully you observe the small changes of fur tone and texture, the finer the hair will look - it depends on how much time you want to devote to the sketch.
You might also enjoy learning how to Draw a Wolf in graphite pencil. You can follow the steps of that lesson using any dog reference photo, too.