How to update Nexus S I9020 to Android 4.2.1 JellyShot Jelly Bean custom ROM

How to update Nexus S I9020 to Android 4.2.1 JellyShot Jelly Bean custom ROM... Now user can update Nexus S I9020 to Android 4.2.1 JellyShot Jelly Bean custom ROM.

Here is the complete tutorial how you can it. Before going to forward, do not forget to backup all your personal data and apps.

Installed all your USB DRIVERS FOR Nexus S I9020 through PC. Some things you should keep in mind.

1. Enable the Debugging Mode. By enable the debugging mode you can connect own android phone with PC.

2. You should check your battery. Your batter should be 80% to 85% charges. If your phone will be off during flashing ROMs or installing mods and updates due to low battery. Then your Phone will be dead permanently.

3. As, i told you. You should back up all your date. You will need it for new ROM.

4. Your Phone should be Unlocked.

Now we move forward and important part.

Here is the complete detail in different steps.

Read the all steps carefully.

Step 1
Download Android 4.2.1 JellyShot Jelly Bean and Google Apps for Nexus S on your PC, if you haven’t already.

Step 2
Connect and mount your Nexus S USB memory on your computer using the USB cable.

Step 3
Now copy/paste the Android 4.2.1 ROM zip and Google Apps zip files to your SD card. Make sure the file is in the SD card root.

Step 4
Then turn OFF your phone.

Step 5
Now to get in the Bootloader Mode. Turn ON the phone while pressing and holding the Volume Up + Volume Down and Power buttons.

Step 6
Follow the navigation instructions on the screen. Select BOOTLOADER and then go to RECOVERY.

Step 7
In ClockworkMod recovery, wipe data first. Then scroll down to “flash zip from SD card” and press the Power button to select it.

Step 8
Press the Power button again and select “choose zip from sdcard”.

Step 9
Now using your volume keys, navigate to Android 4.2.1 ROM zip file and select it using the Power button. Confirm the installation on the next screen and the installation procedure should start now.

NOTE: Repeat this step for the Google Apps zip file as well.
Step 10
After the installation completes, go to “+++++Go Back” and reboot the phone by selecting “reboot system now” from the recovery menu. The phone will boot now and it might take about 5 minutes to boot on your first time. So, please wait.

That’s it! Your Nexus S should have Android 4.2.1 JellyShot Jelly Bean firmware installed on your phone! Go to Settings >About phone to verify.

Now Nexus S I9020 updated to Android 4.2.1 JellyShot Jelly Bean custom ROM.