2. Download cm-9-20120718-NIGHTLY-galaxys2.zip via browser.
3. Verify MD5 checksum 726f573ae5e46d79a25d4488edd2b6b7.
4. Reboot into CWM Recovery.
5. Flash cm-9-20120718-NIGHTLY-galaxys2.zip
6. Wipe cache partition.
7. Advanced > Wipe Dalvik Cache.