Whether you're looking to groom your dog to appear taller because he's just a short pup or because you have a show coming up, learning to do this method takes a little bit of practice. Grooming your dog to look taller will start basically with making him appear thinner. You can also accentuate his slender legs, giving the appearance of height with a good close cut only on the legs. Small fluffy dogs often have long hair on the tops of their heads. Utilize this mop look to increase the illusion of more height.
Your dog may not care how tall he is. Some tiny breeds have the personality of large dogs anyway, so let his personality also shine. But he will expect to be the cutest pup on the block, so do what it takes to please you both. Just as with any grooming, use some treats to reward for good behavior and be gentle with the scissors and clippers.