How to install Cyanogenmod on Huawei IDEOS U8150?

I am installing a custom rom for the very first time and I simply don't want to brick my phone (Huawei U8150). 1. I downloaded and installed Rom Manager 2. I downloaded Cyanogen 7 (update-cm-7.2.0-RC0-U8150-KANG-signed-dec5.zip) for my U8150 and stored it on SD card. 3. I started Rom Manager > Flash ClockMod Recovery > shows a list of supported phones. *It does not have U8150 in the list.* I wonder how others have made it work! 4. From ROM Manager I chosen the Rom file manually with "Install ROM from SD Card" option, it restarts and gives only for options a. reboot, b. apply update.zip c & d. wipe What to do next? The rom file is in .zip, while I downloaded another .img file (clockworkmod_5.0.2.7_u8150.img). What does it exactly do? I think i must first create backup of current rom and then install cyanogen.