How to make this dress more dressy?

Ok so there is this dance at my middle school and its the last dance of the school year. I have searched everywhere and can not find a dress. Since Taylor swift is my favorite singer why not wear one of the sun dresses she designed? I chose this dress in yellow a href="http://www.nitrolicious.com/blog/wp-cont..." rel="nofollow"http://www.nitrolicious.com/blog/wp-cont…/a here is another pic a href="http://i.walmartimages.com/i/p/00/60/97/..." rel="nofollow"http://i.walmartimages.com/i/p/00/60/97/…/a I like the way this girl wears it here but i want it to be more formal a href="http://www.seventeen.com/fashion/special..." rel="nofollow"http://www.seventeen.com/fashion/special…/a so how do i dress it up? p.s. im only 13 so i cant really wear high heels unless they have a small heel haha. If you can Please make a polyvore so i can see it. But if you cant i understand. THANKS :D