How to Make a USB Flash Drive
Bootable With Ubuntu
Ubuntu is a flexible, free and highly functional Linux-based operating system that provides a viable alternative to Windows. In many cases, though, it is handy to maintain Windows or Mac OS X as the primary operating system on a computer while using a bootable Ubuntu flash drive to run a portable version of Ubuntu. This portable operating system is stored entirely on a single flash drive along with your important programs, settings and files, allowing you to move your entire work environment to any computer that supports booting from a USB flash drive. In addition to improving productivity and preventing compatibility issues, this also improves safety, reducing the possibility of having important information stolen or having your files infected with viruses while you are on a public computer.
Boot into Ubuntu. If Ubuntu is not already installed on your system, download and burn an install disc (see Resources), restart your computer with the disk in the drive, and select Live CD mode from Ubuntu's boot menu.
Launch the "Startup Disk Creator" utility by selecting "System" > "Administration" > "Create a USB startup disk" or "System" > "Administration" > "Startup Disk Creator."
3.In the "Source disc image or CD area," select the disc or image of Ubuntu that you would like installed on your bootable flash drive. If you are using a disc, place it in one of your computer's disc drives and select it in the window. If you are using a disc image, click the "Other..." button and browse for the image on your local hard drive or network.
Connect your flash drive to the computer and highlight it in the "USB disk to use" list.
Select the "Stored in reserve space" radio button and drag the slider to select how much space should be reserved on the flash drive for persistent files if you would like your bootable Ubuntu to store persistent data (such as system settings and files) on the flash drive. If you would like your bootable Ubuntu to discard all files and settings each time it is shut down, select the "Discarded on shutdown" radio button.
Click the "Make Startup Disk" button and wait while your flash drive is formatted to boot Ubuntu.
Tips & Warnings
Back up the data on your flash drive before performing this procedure because this information may be erased.