The only thing that is required in order to dual boot is a hard drive with at least 20 Gigs of free space, it will work with a bit less but this is the minimum I recommend.
To get started we need to separate 20 Gigs from the Windows 7 hard drive, to do this we need to create a new partition. You can do this in the disk management MMC snap-in, to launch the snap-in press the Windows Key + R to launch a run box, type “diskmgmt.msc” into the run box.
Once you press enter or click the ok button, a MMC will load with the disk management snap-in.
You are now going to need to shrink the drive C: 20 Gigs for your Windows 8. To shrink the drive right click on the drive C: and select “shrink volume”
A dialog box will appear asking you how much you want to shrink the drive by. It asks you how much you would like to shrink in megabytes, so remember that there is 1024 megabytes in a gig so in our example we shrink 20 gigs which is20480 megabytes because 20*1024=20480.
Once you click the shrink button Windows will shrink your drive. Once it has completed shrinking your partition, the Disk Manager will display this new space with a black header meaning it is an empty partition.
You can format the Partition if you want but is not necessary.The most important thing is to be able to identify your partition from any other partition in your hard drive.So if you need to format and re-name the partition to be able to identify be my guest.
Installation Process of Windows 8.
If you haven’t yet downloaded a copy of the Windows 8 Developers Preview Click here and grab yourself a copy. Once you have burned the ISO to a DVD you might have to into the BIOS and Change the boot order but since you dual booting pre-beta software we’ll assume you capable of that much. If you see the words “press any key to boot from CD or DVD” quickly press any key on your keyboard to begin installation.
Once you have selected your languages then your are ready to install Windows 8. So click the install button to get started.
You will be asked to accept the license agreement, fill the check box and click next to move on to the installation. You should choose the Custom installation option.
Note: You will have to make a critical decision. If you Choose the wrong partition to install Windows 8 it will result in data loss so make sure to choose the one that we created earlier.
Once you have selected the partition, click next. The installation will start.
Once the installation in complete you will be asked to give your PC a name, then click on the next button.
Choose express settings but feel free to choose custom option and specify your own settings.
Create a local account. We want a local account so we’ll click the link that says Don’t want to log in with a Windows Live ID.Then we’ll choose local account on the next page.
Type the name that you want to use as a log on name, also choose a strong password.
Now you can restart your PC to see the new OS Selection screen. By default it will boot into Windows 8 after 30 seconds of inactivity.