How does carslise become a vampire in twilight?

Answer 1

He was leading an angry mob to hunt down a coven of vampires in early London. When they found a real vampire in a sewer, it defended itself by attacking the mob. It jumped on Carlisle first, but he let go and killed the others who were trying to kill it. Carlisle crawled away in pain, so that he would not be killed by the mob (they burned anything that had been infected by the vampire.) Once Carlisle had discovered what he had become, he tried to kill himself. I didn't want to be a monster. He buried himself in potato peels, hoping he would eventually die. But he didn't. So he jumped of tall buildings, and still nothing happened. Soon he decided to starve himself. He was not going to kill others just to keep himself alive. But his thirst became uncontrollable when a herd of deer came by. He acted on his instincts without thinking and killed the deer. He then realized that there was a peaceful solution to this life. He could hunt only animals, and not kill any humans.