Wise people have many wrinkles, but a kindly look. They do not adorn themselves, as a sign they are beyond that, although I suppose they might have a ring or something to signify wisdom.
In men, a pipe with smoke seems wise. They should wear robes of a dark, rich color, hemmed with gold and possibly containing a mandala or other pattern that symbolizes wisdom. Also, they should wear hats. Large, bulky looking hats like turbans. Mortarboards look too ridiculous to me to be wise. I think the hats should be purple. With gold. Somehow the color purple symbolizes wisdom to me.
They should wear slippers with curly toes.
Wise women do not wear hats. They might wear glasses. Their faces should be softened with age. They speak clearly and concisely. They do not smoke. But they might knit. Or crochet. They also wear robes that look rich and heavy, and they wear sturdy, serious shoes beneath their robes, except when they are being playful, and they wear sneakers.