Now get an Ice Cream Sandwich taste on your myTouch 4G via Cyanogenmod9, febycv of XDA Developers Forum has done it. It’s early release of this ROM so you can expect some bugs such as Camcorder, Wallpapers, USB Mount and some more, for that if you still want to install this ROM on your myTouch 4G, just follow below step by step guide carefully, but keep in mind that the below method is risky and we’ll not be held responsible if your device get damage or lose data so try it your own risk:  

To install this ROM your device should be rooted and installed recovery, and you’ll need a USB cable and PC and your battery should be 60% charged. Make a backup of your data because this procedure will wipe all data, turn on USB Debugging, on your homescreen tap Menu> Settings> Application> Development.

Instructions 

Step #1: Download following files: cm9_alpha_glacier.zip & ICS Gapps.

Step #2: Plug the device to PC using USB cable and copy the downloaded zip files to the root directory of your phone external SD card.

Step #3: In recovery mode, create a nandroid backup of existing ROM, if anything should not work out something expected on this ROM, it will helps you to easily revert back to your current state, to create select “Backup and Restore”, and on the screen that follows select “Backup” again.

Step #4: Return to main menu and do a full wipe by wiping the following: Wipe data/Factory Reset, Wipe Cache Partition, Wipe Dalvik Cache.

Step #5: Selecting install Zip from SD card> Choose zip from sd card> then select cm9_alpha_glacier.zip to start installation.

Step #6: Repeat last step for ICS_gapps.

Step #7: Return to main menu and reboot the device. That’s it enjoy!

You can check original thread on XDA here and it its credit goes to Android Authority.

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