What did your pup's parents look like, and the dogs in his pedigree? That will give you a good idea what he will turn out like. Below is my guy and his parent's and uncle. I know he's bicolor and will look like the two bicolors in his pedigree, but only because of the pedigree.
Father is top left, mother top right, my pup bottom left, uncle bottom right. Mother's line has bicolors, father is dark sable, with mostly dark sables in his pedigree.
"An excess of size is an unserviceable feature for breeding, his powers of endurance, his speed and the smartness of his movements suffer in all circumstances. Giants are never nimble."-Creator of GSD