Most of the technical questions, I felt very prepared for. The most difficult questions were behavioral. In particular, "Tell me about an experience where a project partner enjoyed working with you." Rather than talking about your skills you have to talk about how you worked well with others in a way that they enjoyed working with you, and do so without coming off as being arrogant. Also, they didn't ask the question directly, but came to it in a way that put you on the back foot. The question immediately before was to tell them about a time that you had difficulty working with a partner, and also about a time that a partner had difficulty working with you.