Just a quick CentOS tutorial to craete a bootable live USB. I will show you how to create CentOS 7 Live USB from Ubuntu 16.04 using dd command. No need to install any third party software because dd utility is available on Ubuntu and other distro. This process will use Terminal command, its not too difficult to create CentOS 7 Live Bootable USB.
Steps to create CentOS 7 Live USB
Step 1. Download CentOS 7
I am using the latest CentOS 7 1611 ISO on this tutorial. You can obtain this latest CentOS 7 release from this link.
Step 2. Plug the USB Flash Disk to USB port
Please make sure you have more than 4 GB USB Flash Drive. USB 3.0 is highly recommended.
Step 3. Check the USB drive with fdisk command
Open Terminal and check the flash drive using fdisk command.
sudo fdisk -l
As you can see, my USB drive is listed as /dev/sdc. This may different with your situation.
Step 4. Copy the ISO to USB Flash Drive
Still in terminal, now execute the following command to start creating CentOS Live USB. Please change the file name with your own.
sudo dd if=/home/dhani/CentOS-7-x86_64-LiveGNOME-1611 of=/dev/sdc
Wait until the copy process is completed and in few minutes, the CentOS 7 Live Bootable USB should be ready.