First of all, welcome! I'm also new here, but finding it quite rewarding!
You came to the right place - losing 10% of your body weight can make your life and PCOS so much easier. I was diagnosed about a year ago and didn't believe that weight loss can have such an effect. After a bit of a wake up call about 2 months ago, I decided to give "make healthy choices" a chance and it's well worth it.
Having PCOS is hard because it is a "hidden" decease, however the choice to change things lies with you! Stay motivated. We cannot (as yet) be cured, but the symptoms are very controllable. For more support, also check out soul cysters.
Counting calories and regular exercise has been working for me. And also just generally making healthy choices (stairs in stead of elevator, low fat in stead of full cream, etc) adds up to a lot in the long run.
Oh, and I'm almost 25 - good to meet you