i don't know if a jailbreak is available for 6.13, but the last time i jailbroke my shit was an earlier version of ios 6... and jailbreaking was all a matter of downloading a specific jailbreak program, connecting your ios device, and clicking a button on screen, and that was that
whatever the case is, don't worry about fuckin it up... just as long as you back up your device on itunes and making an extra copy of that backup file before you try to jailbreak it...
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