What are some tips for girls high jump in track?

I'm on the track team and I need some tips on how to get better in high jump. I can easily get over 4', and my best so far is 4'3". My goal is 4'6".|||The trick is in the vertical jump, using your arms to throw yourself up, and arch. Make sure that when you land on the mat your body is perpendicular to the bar, rather then parallel to it.