New hairstyles??? Help!!!?

so basically im 13, nearly 14 and im in serious need of a makeover! Im planning to get my hair cut and have a whole new image ready for september. In a few weeks, we will break up for 6 weeks, then in september I want to forget the old me and live as the new me. So do any of you have any ideas on what sort of hair i should have, or if i should cut it at all!? I have a square shaped face, brown hair that comes a few inches below my shoulders and i am olivy/tanned skin. I need a new image that makes me look not like a dork , nerd, chav or anything bad. I want to look older, stronger and prettier...so can you help me??? I would like detail and pics pleasee xxxx