The first things we learn about Darcy at the Meryton ball described in the very beginning of the book is that he is very elegant, very tall, very handsome and has a very aristocratic bearing. We also learn that he his very wealthy, much wealthier than Bingley. At first, everyone in the room is very impressed with Darcy. Austen relays that the "gentlemen pronounced him to be a fine figure of a man, [and] the ladies declared he was much handsomer than Mr. Bingley" (Ch. 3). However, the company at the ball soon decided that Darcy actually had very poor manners. Those at the ball soon decided that he was very proud and thought himself "to be above his company, and above being pleased" (Ch. 3).
Darcy's behavior at the ball certainly helped to prove the general opinion that he was proud and conceited. The company at Meryton found Bingley to be very friendly and lively, unlike Darcy. Bingley acted very sociably while Darcy did not. Bingley soon introduced himself to every important person in the room, "danced every dance," and even promised to hold a ball at Netherfield. Darcy, on the other hand, only danced with the ladies he already knew. He danced with Bingley's married sister, Mrs. Hust, once and then once with Bingley's second sister, Caroline Bingley. On top of that, when Bingley tried to encourage him to dance more, saying, "I hate to see you standing about by yourself in this stupid manner," and tried to persuade him to dance with Elizabeth, Darcy delivers his famous insult. He says, "She is tolerable; but not handsome enough to tempt me." Hence we see that Darcy is certainly characterized as a proud, conceited, disagreeable man and that the other characters in the room were right, at first, to dislike him.