Very few people actually have any idea that they come across as arrogant. You cannot and should not trust your own judgment regarding how others may perceive you. Therefore, you should encourage your friends or anyone else, who you can trust to be honest and direct with you, to tell you if they think you may come across as arrogant. In case your attorney didn't discuss this with you, you should specifically ask him whether he believes you may come across as arrogant. If you have this issue, the good news that you can work on it and it can be eliminated relatively easily - if not from your personality, at least from the way you appear when you testify.