She is describing the boy's uniform which is ornamented with braid, like this:http://tinyurl.com/2xdj3h
I was wondering about the expression braided boy below. Are we talking about hair, or something completely different?
Presently he turned and joined her. "You go right along up to bed--I'm
going to sit down here and have my smoke," he said. He spoke as easily
and naturally as if they had been an old couple, long used to each
other's ways, and her contracted heart gave a flutter of relief. She
followed him to the lift, and he put her in and enjoined the buttoned
and braided boy to show her to her room.
(Edith Wharton - Summer)