We covered the recently released AOSP ROM for the Nexus S running on Android 4.0 and today we'll cover briefly on how you can install it on your Nexus S. The ROM is almost perfect for daily use, the only issue being the broken camcorder, tethering and data usage limit. However things like WiFi, hardware acceleration, GPS, camera, face unlock are working perfectly fine.

You will need a rooted phone for this to work.

Rooting voids your warranty. Not following the instructionscarefullymight result in a bricked phone. Proceed at your own risk!

Instructions

Download the ROM from hereand place it in your phone's mass storageBoot into the bootloader by powering off your phone, then pressing volume down + power at the same timePerform a nandroid backupWipe data and cacheGo to install from zip card and select the zip file you downloadedRestart your phone and enjoy Ice Cream Sandwich!

For more information, updates and troubleshooting, visit this thread on XDA