How to Resize the Windows Partition in OS X

1. Double click the Mac hard-drive icon on the desktop. Click the 'Applications' folder, then select the 'Utilities' folder.
2. Click 'Disk Utility.' The Disk Utility window will open. Click the hard drive in the left pane that you want to configure, then click the 'Partition' tab. The different volumes on the hard drive will be displayed in one box.
3. Click on the handle that separates the Windows partition from the Mac volume, then drag it to resize the partition. Click the 'Apply' button when you have finished resizing the Windows partition.