Tails is a live operating system that you can start on almost any computer from a DVD, USB stick, or SD card.
It aims at preserving your privacy and anonymity, and helps you to:
Use the Internet anonymously and circumvent censorship
all connections to the Internet are forced to go through the Tor network.
Leave no trace on the computer you are using unless you ask it explicitly.
Use state-of-the-art cryptographic tools to encrypt your files, emails and instant messaging.
How to install Tails.
Download Universal USB Installer
Installation on Usb Stick:
Open Universal Usb.
Select Tails from the drop-down list.
Clickand choose the ISO image .
Select the Format option.
HOW TO BOOT:
Plug in you Usb and Reboot “if this doesnt work do the above”
Enter Bios -> Boot Menu -> Set your Usb as the 1st Drive then Reboot.