Before installing Ice Cream Sandwich (ICS) on Samsung Galaxy SII (SGS2), your handphone must be rooted. Read this article for rooting SGS2.
- Download ICS firmware from this website. You have to register first before able to download.
- Still on sammobile.com website, download Odin downloader.
- Extract both files and open Odin. Check Re-Partition option. Press PIT button and locate .pit file inside Odin folder. Press PDA button and locate .tar / tar.md5 inside firmware folder. Press Start button.
- Once finished, phone will be restarted in ICS Android 4.0.
- It’s done.