Any tips for senior pictures?

1. Should I keep my hair naturally straight?
2. Ideas for outfits? Casual or a bit formal (dresses, etc.)?

And also, should I have my friend take pictures of me with a her Nikon camera? Or should I go to another person who actually does it professionally but pay $100 for it? I'm not familiar how much other companies charge for photoshoots, since I know the photographer personally; it's even at a discounted price.

Be yourself.

And remember, you get what you pay for.