Download iOS Firmware From HERE
Put All File's in One folder
Use Window7(it's just less buggy)
1: Open Redsn0w Go to Extra->Even More->Restore
2: Click IPSW And select IPSW
3: If you have SHSH in computer Select local,If your SHSH on cydia click Remote(I did Remote),If you want to submit saved shsh from computer to cydia open RedSn0w go to Extra-> SHSH Blobs-> Submit.
4: Note the Software version(5.1.1) and baseband version(2.0.12) Shown in picture below.
5: Now Redsn0w will start it's work.
6: After Completing initial process Redsn0w will popup a message About baseband update,Read and select Yes.
7: Redsn0w start restoring system image.
8: Redsn0w Updating baseband version.
9: Restore Done Successfully
10: Note the Software version(5.1.1) and baseband version(3.0.04) Shown in picture below.
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