Gwyn, Lord of Cinder, is a powerful and ancient being who once ruled over the world of Dark Souls. He has a majestic appearance and clothing that reflect his status as a king and a god. According to the web search results123, he wears:

A set of royal drapes with gold bands on his arms and a crown atop his head.
A pair of boots on his feet.
A greatsword imbued with the power of light and fire, which he uses to strike down his enemies.
His face is that of an old man with calm eyes, a long grey beard and hair. However, when he is encountered in the Kiln of the First Flame, he appears to be hollowed, with charred skin and missing eyes. He has sacrificed himself to prolong the Age of Fire by linking himself to the First Flame