Installing windows 8 along side any other existing Operating System can be little tricky if you have not done anything like that before. You need to setup partitions,assign drive letters and all those stuffs. Let me show you all these things in as simplified manner as possible.
Lets start by creating partitions.
You need to be logged in to your Primary Operating System to continue.
Note: It is highly recommended that you take backup of your files before partitioning.
Step 1. Download and Install Easeus Partition Manager. [LINK] (Choose the Free Home Edition)
Step 2. Start the Software > Go to main screen > Click on a partition that has atleast 30GB of free disk space and which you can split.
Step 3. Click on Resize/Move partition from the Top Menu > Move the slide from left until you have 30000 MB in Unallocated Space Before.
Step 4. Click on Ok > Apply.
Step 5. You might have to restart the System in order to complete the operations, So remove any USB Disk or CD/DVD and Click on Restart when Easeus prompts.
Step 6. After restarting, Your system will go through a series of steps like Moving the Data, Resizing, Assigning Drive Letter etc, So be patient unless all of them happen. NEVER restart the system while the partition is undergoing, It might lead to Boot problems and Corrupt data.
Step 7. Once the system has rebooted > Check your My Computer and you will find a new Empty drive with 30GB space. Hence our partition is created.
Dual Booting Windows 8.
Installing Windows 8 via DVD.
Step 1 (a). Download and Install Free ISO Burner software [LINK]. (Recommended over default Windows DVD Burner)
Step 2 (a). Click on Open near the ISO File option > Select your downloaded Windows 8 ISO.
Step 3 (a). Set the Burn speed to 4x to avoid any Errors while burning the disc > Burn > Keep the DVD inserted > Restart system.
Step 4 (a). Set the First Boot Device as CD/DVD drive in the BIOS options (mostly accessible by Pressing Del or F2 before the Manufacturer Logo Splash just after Power ON of machine.)
Installing Windows 8 via USB.
Step 1 (b). Download and Install Microsoft Windows USB/DVD Download Tool. [LINK]
Step 2 (b). Open the tool > Select the Windows 8 ISO file by Browsing.
Step 3 (b). Select USB Device > Begin Copying.
Step 4 (b). After the copying is finished > Keep the USB inserted > Restart system > Enter Bios > Set the External USB device as first boot device and continue with the Setup by answering the installation prompts and setting boot partition.
After the setup has been completed. Next time you restart the system, You have to choose the Operating System from the boot menu. There are other options which you can play with
Hope you liked the article.