What do others say about Holden? Please give examples.

This is a tricky question because Holden is the narrator of his story, so anything anyone else says about him is filtered through Holden himself as he explains his interactions with the other people. With this fact in mind, here are three examples of what Holden says others say about him.
Holden meets three older women in the Lavender Room, and the blonde that he dances with criticizes his bad language when they talk. According to this blonde woman, Holden uses inappropriate language much too often. She says to him, "Watch your language, if you don't mind" and then later, "I don't like that type language" when Holden says "Chrissakes," and she threatens to stop talking with him if he keeps up his blasphemy.
When Sally and Holden go ice-skating, Holden gets very animated and energetic when speaking with Sally about school and the pointlessness of his experiences at all of his various schools. Twice, Sally asks Holden to stop shouting and to lower his voice, which annoys Holden, who claims that he wasn't raising his voice at all. The fact that Sally says Holden is being loud suggests that he does in fact raise his voice in an aggressive way when he gets worked up about a topic.
When Holden meets up with Luce—his old Student Adviser at Whooton—at the Wicker Bar in New York, they engage in what Luce describes as a "typical Caulfield conversation" about girls and sex. When Luce reveals that he is involved with a woman from Shanghai, he describes the Chinese approach to sex as both "a physical and spiritual experience," which leads Holden to say that he would like to go to China. At this point, Luce describes Holden as having an "immature mind."