Updated to iOS 6 firmware your iPhone, iPad or iPod touch then its time to save you iOS 6 SHSH blobs for future downgrade or jailbreak purposes. When Apple stops signing a firmware, it is impossible to restore that firmware unless you have SHSH blobs saved for it. Firmware downgrade is not possible without SHSH blobs for the targeted firmware.
If you already jailbreak your iPhone, iPad or iPod touch running iOS 6 then you can save iOS 6 SHSH Blobs by visiting Cydia. If you are not yet done jailbreak on your iDevice then to save SHSH blobs TinyUmbrella v6.00.00 can be use. Both jailbroken or un-jailbroken devices’s SHSH Blobs can be saved with TinyUmbrella v6.00.00.
How To Save Your iOS 6 SHSH Blobs & Submit To Cydia Servers:
Step 1: Download TinyUmbrella v6.00.00 from this link and latest version of Redsn0w v0.9.15b1 from here.
Step 2: Install TinyUmbrella v6.00.00 and save your SHSH Blobs.
Step 3: Now install Redsn0w v0.9.15b1 and go to Extras>SHSH blobs>Submit from the main menu.
Step 4: Select your iOS 6 SHSH blobs files and Redsn0w v0.9.15b1 will automatically submit to Cydia servers for future use.