Make sure you follow the instructions for BootCamp to the letter.
You CAN seriously hose your system if you don't follow them properly. You DON'T have to format your drive yourself. If you're using OS X on an Intel Mac then all you do is run Bootcamp, it will guide you through and allow you to "live partition" your drive as you go.
Print off the Installation Guide in the post from HowEver. It will be your saving grace.