Mac OS X, despite being one of the most intuitive and user friendly OSes on the planet, adopts a very obtuse procedure when it comes to formatting a USB drive. Every single time you get a new USB drive it comes formatted in FAT32. Of course, Time Machine will only work on a drive formatted as Mac OS X. So, pop open Disk Utility, select the drive and hit the ‘Erase’ tab… only to find out Disk Utility refuses to erase a FAT32 drive. Grrr. Instead of the ‘Erase’ tab, select the ‘Partition’ tab in Disk Utility, click the drop down for ‘Volume Scheme’ and select ‘1 Partition.’ Name the disk in the box provided and, on the drop down format box, choose ‘Mac OS Extended (Journaled).’ Hit the apply button, and a pop-up appears warning you that you are about to erase the disk (finally!) hit continue and you are on your way.