Step 2: Run the TinyUmbrella.
(Mac users: Copy the app to your desktop or you’ll get repeating password prompts if you ran the app from within the DMG).
Step 3: Now Connect your iPhone 4, iPhone 3GS, 3G, iPod Touch 4G, 3G 2G, iPad or Apple TV 2G to your computer. TinyUmbrella will detect your iDevice.
- Make Sure iTunes is closed
- Now Simply Hit the Save SHSH button at Top-Right side of the window.
TinyUmbrella will save SHSH blobs of the latest firmware + all those blobs that you had saved for older firmwares (if any) on Cydia server. This will also generate a ticket to save SHSH blobs for the latest firmware to Cydia server.
Step 5: All Done! You have secured your future jailbreak by saving SHSH blobs for iOS 4.2.1 using TinyUmbrella. You can find the saved SHSH file directory under advanced Tab on TinyUmbrella and Cydia will also display your Saved SHSH blobs/status pending. [Via Technobolt]