iphone 3gs upgrade from 4.1 to 6

[akashay]

i m having iphone 3gs 16 gb at 4.1 version i want to upgrade it how to do itt

[jamesjerss]

i have the same problem,got software unlock and they downgrade it from 6.1 to 4.1 ,now i cannot use facebook on it and all other usrfull apps.need help on that.

1st make custom firmware 6.1.3 using snowbreez but its tethered jailbreak. while creating custom firmware select simple mode nd select hackactivate . snowbreez will extact ibooty n yur desktop it vil usefull at last. Den install itunes version 10.5 or 10.6 or older bocz itunes 11 will not allow to restore custom firmwares after create custom firmware put yur mobile into Dfu mode snowbreez wil ask . den launch itunes press shift key n yur keyboard nd press restore show the firmware path . after restore complete yur mob vil not boot . use ibooty to boot yur mob . After boot yur mobile opn cydia search p0sixspwn and install now yur mobi on untethered jailbreak .now search ultrasnow nd instsll.