Get an e-mail first about completing an evaluation test online. Then I had my one on one interview which was mainly behavioral interview questions that lasted about one hour. They judge based on the results of the evaluation test, interview, and your resume.

The interview lasted about an hour, and it was very easy going. However, none of the typical behavioral questions came up. Almost every question was situational, e.g., "tell me about a time when..." so all the preparation didn't help. Just be confident with your knowledge and experience. Despite the questions, the interviewer was very friendly and it really just felt like a conversation.