Berserker, as Hyde, has an appearance similar to a werewolf with black fur covering his body, a large jaw, sharp fangs, and a beast-like, humanoid form. His eyes glow upon seeing the full moon.
As Jekyll, he is shown to be fancily dressed in a white dress shirt, an olive green vest, and a black and grey jacket draped across his shoulders. He wears a black and white handkerchif with a red jewel around his neck, and leather gloves over his hands.
(Source: Type-Moon Wiki)