Help?

just be yourself. doing that makes him know that he's meeting a normal girl, not another pop 별, 스타 또는 something which maybe makes him feel 더 많이 comfortable. if 당신 act like someone else while meeting him, maybe 다음 time when 당신 meet up with him again, 당신 will have to act again, which is totally uncomfortable. so, why suffer the uneasiness when 당신 can enjoy an awesome time with Justin Bieber?

First of all, congratulations! As far as your behavior goes, I'd try and tone down the extremes (the yelling and what I would call excessive smiling and laughing). And on the other hand, I think Justin's getting used to girls he perceives as excentric. So I'd try not to be overly concerned with embarrassing yourself.