Install windows 8 - Asus S56C

Hi. So, I am helping someone to reinstall windows 8 on an asus s56c laptop. All partitions has been deleted prior to me taking over, due to a failed downgrade to windows 7. I was asked to "fix" it, and reinstall windows 8. The laptop has a 24Gb SSD plus a 450Gb regular mechanic harddrive. 24Gb is too small to use as operating drive, so I assume it has been used to cache the OS. Anyways, I...