Q:

Creating a separate partition for data

I have an SSD (256 GB) and a HDD (500 GB). Currently, I have Windows 8 installed on the SSD and Ubuntu taking up the whole of HDD. I wish to create a separate partition in the HDD (of approx 300 GB space) such that both Windows and Ubuntu can access it. 
I know that it has to be an NTFS partition. What I wish to know is where should I be creating this partition from - Ubuntu or Windows? Also, what's the best to go about doing it. 
Here is the present situation :

A:

You could use Gparted on Ubuntu do do the job. Follow these instructions:
1 -  Back up anything really valuable. This is a pretty tried and tested formula but things can go wrong. A power cut at the wrong moment could really ruin your day if you haven't backed up.
2 - Boot to a LiveCD or LiveUSB drive in "try me" mode.
Load gparted (should be installed by default, you can apt-get it if it's not)
3 - Resize your partitions (right click, click resize, follow the instructions).
4 - Click apply and sit back while it does the job.
5 - Reboot, taking out the USB stick or CD when it tells you to.
from Oli's ANSWER
If you do not already have Gparted you can get it HERE, or by typing in Terminal :
sudo apt-get install gparted

