Blackbeard is a middle-aged looking man with a massive build (his body is round with relatively thin limbs), a big mouth with several broken or missing teeth (though sometimes he does have a full set; whether this is an inconsistency error made by Oda or part of the story is unknown), a pronounced crooked nose and a very large and hairy chest and torso. Long, thick, curly black hair falls down the back of his neck, underneath a black bandana, and a small scruffy black beard (hence his epithet) grows around his jawline. As the series progresses, his beard becomes longer and scruffier. He is extremely tall, being exactly twice Luffy's (pre-timeskip) height.
At his first appearance in Mock Town, Teach wore an open buttoned white shirt with rolled up sleeves, green trousers with black line patterns, a yellow sash around his waist and classic black swashbuckler boots complete with large bronze buckles.
During his raid on Banaro Island, he had added a large black and gold captain's coat over his attire, along with white beads on each wrist as bracelets and rings with gemstones on all of the fingers of both his hands (similar to his predecessor, Crocodile).
At the Shichibukai meeting at the Marine Headquarters, he added a pair of necklaces of red as well as golden-yellow and blue beads to his dark orange sash and a traditional black tricorne hat over his grey bandana, as well as switching to a red shirt. He also has three flintlocks and a flask tied to his sash around his waist.
In the Volume 63 SBS Oda drew the Shichibukai as children. Teach is shown wearing a baseball cap with a rolled up long sleeve shirt and green shorts. He is also wearing black curled tip shoes, and unlike his usual cheerful expression, is crying for an unknown reason.
After the time skip, Teach has grown a long beard that he has split into multiple sections, very much like his real life basis. This has only been shown on a Den Den Mushi.