How To Format a USB Disk for Use in a Mac and PC Environment. Using a Mac, How To format a USB disk to use on computers running Mac OS X and Windows.
Open the Device Manager and find your USB drive under the Disk Drives heading. Right click the drive and select Properties. Choose Policies tab and select the 'Optimize for performance' option. Open My Computer; Select Format on the flash drive. Choose NTFS in the File System dropdown box. Click Start button and wait until finished.