Linux live CDs, or USB versions are a great way to test and enjoy any Linux distribution available. But there is a problem, with CDs you are Unable to save data and the CDs are extremely slow. So you can experience everything we want, but when you save a document, or even download a program, here you are required to install the OS, or just resign ourselves to make the disk, and return to our daily tasks.
Linux Live USB Creator solves this problem by giving us the ability to add a space “persistent” in the USB. Therefore, we can burn files, download Applications, And using our Linux USB as if the primary operating system, With one limitation: we can not do OS updates (kernel updates): ie at 6 months if the new Ubuntu comes out, we will have to reinstall the entire OS in our USB. But this limitation is minimal compared to the benefits of having a USB with Linux, with the possibility of saving data. Above all there is almost no chance of attack of virus or any other malicious program with Linux.
Before seeing the steps in to be followed its best to download the application, Linux Live USB
Step 1: Prepare USB/Flash Drive

Choose the USB Drive. Be sure to choose the USB will be used properly.
Make sure you have a USB for at least 1 GB space (for most distributions).
Make sure it is formatted in Fat32 or Fat (preferably FAT32)
Step 2: Choose the source

Here we mean what we want to install Linux distribution. If you downloaded the ISO from the official website, simply choose ISO. If you have a disk, just the CD option. To Download, we will have a list of distributers of linux available, among which are:
- Ubuntu / Kubuntu / Xubuntu 9.10
- 10/04 Ubuntu Alpha 2
- Jolicloud
- Puppy Linux
- Gentoo
- Android (yes, the smartphone operating system)
- Linux Mint, one of my favorite distros
- Fedora 11 / 12
- many more
Step 3: Persistence

Now, the pace of interest. Here we can enable the option to Persistence (displayed once we have downloaded the Linux distribution, or chosen an ISO). When it appears, can put a percentage of space (300-500 megabytes is recommended unless you install many programs and files), for use as persistent memory.
Step 4: Final Stage

LinuxLive option allows us to load the USB from the same Windows Without having to reboot (one mode to the virtual machine), besides, of course, you can load the USB directly.
Finally, we have the icon of the beam that starts with creation. Wait a few minutes, and voila!
Now we must set our PC to load first the USB.
Finally We will have our USB ready, with Linux, even capable of not only save our documents, applications, and data, but we can also load it from Windows, without rebooting!
via: arturogoga.com