In desperate need of hair help

Hey everyone!! I need help bad. This fall I will start college and I am in desperate need of a makeover, hair wise. I look really young for my age; I am constantly told that my younger sister looks older than I do. I need a hairstyle that will make me appear my actual age. I am getting ready to turn 18 and I just want to look that way. To make things even worse I am also very small body wise. I am hoping that a good haircut can help me out a little. I am tired of looking like I am only 13. Can someone help me please?
Oh, BTW, My hair is naturally curly, but I do straighten it. It is to my shoulders now and thick.
Thanks in advance,
Tonya

Maybe a shorter, shag haircut to play up your curl would make you look more sophisticated. My daughter has the opposite problem--she is only 15 and people (guys especially) think she is over 18. She wears make up and earrings and has long straight hair. Her clothes help though. She likes to dress well and has very sophisticated taste. Have fun at school and I think the previous post which stated you won`t have much time to worry about how you look is correct. But you are only young once and that will take you a long way.....

Perhaps what you should do is not bother straigntening it, but using one of those hair bands that pull
back the hair, making it more or less straight as far as it goes back on the head, and keeping it off the
face.