What are the visual elements where the winners enter the competition?

The primary description is that of the elusive Willy Wonka himself.

Mr Wonka was standing all alone just inside the open gates of the factory.
And what an extraordinary little man he was!
He had a black top hat on his head.
He wore a tail coat made of a beautiful plum-coloured velvet.
His trousers were bottle green.
His gloves were pearly grey.
And in one hand he carried a fine gold-topped walking cane.
Covering his chin, there was a small, neat, pointed black beard — a goatee. And his eyes — his eyes were most marvellously bright. They seemed to be sparkling and twinkling at you all the time. The whole face, in fact, was alight with fun and laughter.
And oh, how clever he looked! How quick and sharp and full of life! He kept making quick jerky little movements with his head, cocking it this way and that, and taking everything in with those bright twinkling eyes. He was like a squirrel in the quickness of his movements, like a quick clever old squirrel from the park.
Suddenly, he did a funny little skipping dance in the snow, and he spread his arms wide, and he smiled at the five children who were clustered near the gates, and he called out, 'Welcome, my little friends! Welcome to the factory!'
His voice was high and flutey. 'Will you come forward one at a time, please,' he called out, 'and bring your parents.