First we'll need to grab Fedora's liveusb-creator tool by grabbing the zip file listed under "Download," extracting it and running the liveusb-creator.exe file found inside in Windows. You can download Fedora's liveusb-creator at https://fedorahosted.org/liveusb-creator
The top options on the window let you choose to use a live Fedora CD image you've already downloaded or have the tool grab a copy of the standard Fedora 9 disc itself. If you'd rather grab the file yourself or download it through a torrent, use one of the links listed under "live media" at the Fedora Project. Plug in your USB drive if you haven't already, and make sure it's selected in the "Target" field. Don't worry about files you've got on there—as long as the tool has space to put Fedora on there, it won't touch your other files.
The slider to the right is the most important part—"Persistent Overlay" is the space on the thumb drive you want to use for storing your files and settings. The Fedora system itself is going to take up roughly the size of a stuffed CD; using an empty 1GB thumb drive, I chose 205MB for the overlay, which left 63MB free, but you can scale that up for larger drives or down if you want more free space. Keep in mind that any files you store on the drive itself can be accessed from inside your USB-booted system, so a bigger persistent overlay isn't always necessary.
Hit "Create Live USB," and watch the creator do its thing. Once it's done, your stick is probably ready to get plugged in and booted up.
Now you should be set to boot into Fedora 9. You'll see a splash screen counting down from 10 when you boot (hit Enter twice to speed it up), and you'll land at a desktop that's pretty much a fresh Fedora 9 install. You can access to your USB drive's files from here, connect to a wired or wireless network with the icon in the upper-right system tray, and you've got a solid set of built-in applications—Firefox 3 Beta 5, the GIMP, Pidgin, the Transmission BitTorrent client, and a pretty nifty Bluetooth manager, to name a few.
Want to add Thunderbird or OpenOffice.org? Head to the upper-left menus and click to System->Administration->Add/Remove Programs. Anything you install goes into your "persistent overlay," so as long as you've got space for it, you can add whatever you'd like.
Now it's time to explore and get familiar with a GNOME-based Linux system (or KDE 4, depending on which image you grabbed). Here are a few suggestions on helpful tweaks you might want to make once you're set up:
* Enable your NTFS drives: If you've loaded a USB Fedora on a system with Windows installed, you'll want to open up Add/Remove Programs, search for "ntfs-config," and install that package. From the System menu again, choose NTFS Config, and you can select the drives you want to have access to.
* Sync data with your Windows apps: Once you can see your NTFS drives on your desktop, you can use your established settings in Firefox 3, Thunderbird, Pidgin, and other apps if you're booting on the same system as Windows. Check out our guide to dual-booting with shared data; if you're using Firefox 2 in Windows and only want to replicate bookmarks in Fedora, the GMarks synchronizer has updated to support versions 3 and 2.
* Turn off annoying system sounds: One misstep Fedora makes, at least in my opinion, is enabling by default a slew of little chirps and whistles every time you click or do something. To silence them, head to System-Preferences->Hardware->Sound, click the "System" tab, and un-check the "Enable system sounds" box.
You've now got a portable system that's great for rescuing un-bootable computers, bringing your favorite work apps on the go, or just testing out Linux with realistic performance and custom options.