You have these USB headers on the motherboard: http://www.motherboards.org/images/reviews/motherboards/1694_p3_18.jpg?
The case already has the USB ports installed on the front. You just need to connect them with the cable attached to the front usb ports to the USB header on the motherboard.'USB 3.0 looks different from USB 2.0.
What motherboard are you getting? Model number and brand?