A USB flash drive or a portable hard drive are very useful devices for storage and sharing. But there are some problems, cause what would happen with the files if you lose the stick? Somebody could just access the files, without having to know somebodies password. That’s why we are going to teach you have to secure your USB flash drive, by adding a AES-256 bit encryption disk image.
First you have to launch ‘Disk Utility’ (applications -> utilities), and choose your USB drive and the option on the top “New Image”. Now choose the size you want and select the ‘256-bit AES Encryption’, which can be found under Encryption. And press create.
You will now be asked to enter your password, which you want to use to unlock your USB drive. Files that you will be saving on the volume will now be automatically encrypted. You will have to enter the password if you want to see the files on a other computer, you can however also add it to your keychain of your own computer. But on unknown Mac you will always be asked.