The Vampire tends to resemble the person it was in life. However, the Vampire of legend is a walking corpse. Its body might be bloated, the skin stretched tightly across the creature’s body. The Vampire’s fingernails and toenails have grown since the creature’s burial, now sharpened talons. The skin tends to have a pale pallor to it, while being somewhat decayed. Since the Vampire tends to feed on its own flesh while struggling to leave the grave (known as manducation), there are often chunks of flesh missing from the limbs. The creature has sharp, extended canine teeth (the fangs), which allow for easy feeding (although many Vampires in folklore don't have fangs at all!). The Vampire’s breath reeks of decay and coagulated blood (although getting close enough to confirm this is next to impossible). The Vampire tends to be dressed in its burial shroud or whatever clothing the body happened to be wearing at the time of burial, and the creature itself reeks of death and grave dirt. The Vampire’s eyes are fiery red, and the creature’s ears are grotesquely stretched and pointed. The Vampire of ancient times is a horrifying monster, a far cry from the modern interpretation of the Vampire.
For a visual of what I imagine this creature actually looks like, click here: The Vampire (The Demon Hunter's Handbook).