I AM NOT RESPONSIBLE! MAKE SURE YOU HAVE 50% OR HIGHER CHARGE!
Step 1: Explaining Differences between Tethered & Untethered
Untethered is where you can turn your device off and the jailbreak still works, which is not available at this time due to all the security on ios 6 that hacking teams are trying to crack and find exploits, tho 6.2 and under allowed untethered thanks to the evasion team!
Step 2: Required Files
iOS 6.0(NOTHING ABOVE OR BELOW CRUCIAL!) : http://www.felixbruns.de/iPod/firmware/
And for this, the tool being used will be Redsn0w (a common tool in the jailbreaking world)
http://www.redsn0w.us/2010/03/download-direct-links-jailbreak-guides.html (latest version recommeded!)