You don't. Assuming you had a copy of XP which was obtained legally, then odds are good that you won't have all the necessary drivers to make the system work well. It's a myth that Windows comes loaded with all these drivers.
More than that, XP is on life support now, and even that is set to end soon. You are MUCH better off, for many different reasons, running an actively supported OS. Also, Asus is unlikely to offer any kind of technical support so long as you have XP installed on the netbook.
But if you want to find these things out on your own, then you need to do a little research on how to install XP on a SATA HDD.
Hi, Today i buy a asus 1018p and it has installed windows 7 starter. I like to install windows xp so i make my usb with usb multiboot 10 and i start installing xp so i installed many notebok in thIs way but at this pc when windows xp start and load drivers it show a BLUE SCREEN: stop error code 0x0000007B HOW CAN I FIX THIS I WILL GIVE A PAYPAL WITH 13$ WHO WILL HELP ME>>>??????

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