In the case of the Windows 8 support, it's special, because Boot Camp drivers for Windows 8 (Boot Camp 5) are available from the Apple Support website > http://support.apple.com/kb/DL1638 Look at the right part of that site to see that your Mac is compatible. If your Mac isn't compatible, don't download them, and you won't be able to make Windows 8 run properly.
If your Mac is supported, just download the drivers from there and follow the steps on that site to burn them into a USB drive. Then, just open "Boot Camp Assistant" app and follow the steps to install Windows as usual. After installing Windows 8, install the Boot Camp drivers you have downloaded.
Apple has decided to release the Boot Camp 5 drivers on its Support page, so you don't have to upgrade to OS X Mountain Lion in order to be able to install Windows 8 if you have a compatible Mac. See > http://support.apple.com/kb/HT5634