In Mac OSX, how do I create a partition on an unused part of an external hard drive? Half of my 250 GB hard drive is an NFTS partition, and I would like to format the other half for Mac. I'm new to Mac, however, so I'm lost on where to look. BTW, if this is a repeated topic, I'm sorry, I tried searching the forums but could only find stuff on boot camp. Any help is much appreciated!