

When you get it, it probably won't be formatted for your Macintosh, so plug it in and run Disk Utility (in /Applications/Utilities) to format the flash drive. To make a diagnostic and repair flash drive, I'd suggest buying an 8 GB flash drive, 16 GB flash drive which can be had for around US $20 US $35 these days. Time Machine makes it so easy that not having a backup plan is just silly. This is not meant to replace or in any way affect backing up your hard drive. You can prepare for this by creating a bootable flash drive containing some diagnostic and repair utilities. If your hard drive tosses you errors, behaves badly or doesn't even appear, what to do? If programs crash at random, you need to be ready. It's a good idea to have a strategy in place in case of emergencies. I'm very sorry for any inconvenience this has caused. According to readers, installing Snow Leopard on an empty flash drive will take 8.01 GB requiring a 16 GB flash drive. As a few of our commenters pointed out, and as is the case, in testing I erroneously tried to install Snow Leopard on a flash drive that already had a version of OSX on it, making the installation much smaller than installing on an empty flash drive. I was incorrect in writing that an install of Essential System Software would take 3.81 GB. Update: You cannot install Snow Leopard on an 8 GB flash drive. More Mac 101, our tips and tricks for novice Mac users.
