Step 2 - Partitioning
Our method of setting up multiple boots requires setting up a separate and new partition for each boot operating system. Let's get started on this part by booting into Windows 7 and then clicking Start, Control Panel, "All Control Panel Items" at the bottom right and then click Administrative Tools, Computer Management, Storage and then finally Disk Management.
You will be greeted with a screen similar to the one above. N.B. we have already setup our partitions; you still need to do that now.
In Windows XP this wouldn't be possible and you'd need to buy a standalone application such as Partition Magic; but in Vista and Windows 7, Microsoft thankfully added in quite a few disk tools for messing with partitions, sizes and so on. What we are going to do now is shrink your Windows 7 partition (or volume) size, to create space for installing our other operating systems.
To do that, right click on your Windows 7 volume / partition ( as seen above), and click Shrink Volume.
The next step is to determine the size of the new partition that you are creating. For Windows Vista SP1, we recommend at least 20GB as a safe number and for Windows XP, we recommend at least 5GB, which is also a little over what you actually need.
So, as you can see in the screen above, enter the amount of space to shrink your Windows 7 volume in megabytes - we setup a new 50GB volume for Windows Vista, which is 51200MB (50 x 1024). Once you've entered the amount of space, click 'Shrink'.
You will then be greeted with your new partition, unformatted and unallocated. You can have Windows Vista and XP installs do this for you, but we'll do it now, just to confirm everything is working and that you've followed the guide correctly thus far.
The next step is right clicking on the new partition and clicking 'New Simple Volume', as you can see above.
Leave the volume size as is and click 'Next'.
Here you can assign the drive letter for your new partition - we recommend you leave it at whatever Windows suggests and then click 'Next'.
Now we are up to formatting the new partition and creating a volume label (or name) for it - you will also want to make sure you keep the file system set as NTFS, unless your operating system has specific requirements for another. For simplicity purposes, label it the same as whatever operating system you wish to install on it, so it is easy to recognize when installing your OS. Ensure you click 'Perform a quick format', otherwise it will take a long time to do a full format - then click 'Next'.
Your partition is almost ready, click 'Finish'.
Here you can see that your new partition is being formatted. Once the format has completed, a new window will pop up in Windows Explorer with your new drive. It will be empty and that also confirms for us that you've followed the guide correctly up to this point.
Depending on which operating systems you want to multi-boot, you will want to apply this above process again. Just do the same by shrinking your Windows 7 volume and you'll be just fine.
Here you can see our "dummy" partition is fully setup and ready to go for installing the OS.
Here you can see the partitions fully setup under My Computer. And now that our partitions are fully setup, we are ready to begin installing our operating systems!