Most Helpful Girl
Get a really cute haircut, like maybe bangs or side bangs if you didn't have them before. The different hair color and length is good.
If you wore a lot of makeup before, keep it subtle now. Or if you didn't wear any before, wear some nice natural makeup.
Sounds like you're more grown up now so I'd say completely change your style of clothing. Like if you were tomboyish or casual or really girlie before, wear more grown up styles now. Simple nice jewelry, heels if you didn't wear them or flats if you did, dresses if you didn't or nice jeans if you used to wear more dresses and skirts. You get the picture.
I think really looking like you've grown up and matured will make you look attractive and show people that you've got your life together.