Doing so has several advantages. You can, for example, preview Windows 8 without fully committing to it, making use of the fun touchscreen-enabled apps in the Metro interface when you want to view photos, create doodles or play casual games. The familiar version of Windows you use everyday will be there after a simple reboot, and you can use the Consumer Preview until early 2013. You don't need to worry about hardware compatibility either – you'll still have your old version of Windows and Microsoft has checked that anything that runs in Windows 7 will do so in 8.
To partition your drive you'll need a fair chunk of available disk space. The new operating system requires at least 2GB to install, not to mention storage space for any documents and folders you create while using it. Work on the assumption that you'll need between 10GB and 20GB to install Windows 8, and have enough room to store and save photos and videos you run on it.
Also note that you'll need either a blank, writable DVD or a USB flash drive you don't mind formatting. Here' we've used a USB drive to install Windows 8 on a Toshiba Ultrabook (which has no optical drive), but the process takes longer than when we dual-booted a Toshiba laptop and installed from DVD. See also: Install Windows 8 Release Preview.
Windows 8 downloads:
Step by step: how to dual boot Windows 8
1 First, check how much space you can use for your partition. Go to Control Panel, Disk Management and right-click on the drive you want to partition. Windows will determine how much unallocated space is available. You'll use this to create a new, ‘Simple' drive.
2 If you find there's very little available space, check whether your existing drive allocation can be reduced. Right-click on the pane relating to it to see whether it can squeeze up a little. We also found it helpful to run a Disk Cleanup as this also freed up unallocated space.
3 Right-click within the unallocated disk space pane in the Virtual Disk utility and select ‘Create new Simple drive'. You can choose between FAT and NTFS drive types. Stick with the latter and click to proceed. Either accept the default drive name such as E or type in your own. Allow Windows to perform a quick format of the existing content.
4 Head to Microsoft.com and enter your email address and other details. You'll now be able to download Windows 8 or the Consumer Preview file to your hard drive. Once it's downloaded and gone through its compatibility checks, enter the product key. For the Consumer Preview this is: DNJXJ-7XBW8-2378T-X22TX-BKG7J (this should also appear onscreen).
5 Windows will ask whether you want to install it immediately. Choose the option to install it to another partition. You now need to save the Windows 8 ISO file to an external device. Here, we've used an external hard drive. It needs to be at least 3GB. Since it will be formatted for use, delete anything you need.
6 A message momentarily appears informing you that Windows 8 can now be installed from the USB drive. You now need to change the boot order that your PC uses. Restart the PC and, as soon as it begins to whirr into life, press F2. In the resulting Bios menu, use the arrow keys to find the current boot order list. Press Enter to accept the settings and exit the BIOS menu.
7 Allow Windows to continue to load if the DVD with the new OS is already inserted. Otherwise, insert the disc containing the ISO file and restart. A black BIOS screen telling you to press any key to proceed to boot from the DVD will appear. Windows 8 will announce itself with this screen.
8 Click ‘Install now' to proceed. Select ‘Custom install' and ensure you choose the new partition (the one labelled E, F, or so on), so you don't overwrite your existing Windows setup.