How to install rom zip 4.0.4 Sony ST18i ( xperia ray )

I. install ClockworkMod:

    Install X-Parts from Google Play.

    After installation, open the app and select the Installs tab.

    Select Install CWM and follow on-screen instructions.

    You can Reboot into the recovery mode from there (press the button in the Tools Tab)

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II. install boot.img:

Now you need to install the boot.img from the your rom Zip:

    Connect your device into fastboot again with Vol-Up While plugging in the USB-Cable
    fastboot devices
    (Seeing your serial number means we know all is good.)

    Now type these commands:

    fastboot erase system -w
    fastboot erase boot

    then copy the boot.img in the same folder as fastboot.exe and type

    fastboot flash boot boot.img
    fastboot reboot

    Now press the Vol-Down Button to enter the Recovery Mode again and install your image

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III. Install your rom in Recovery Mode:

    Once the device boots into the ClockworkMod Recovery, use the physical volume buttons to move up and down. On most devices, the power button is used to confirm your selection, although for some devices the power button is used as a "back" button to go up one level, in which case the home button is used to confirm the selection.
    Optional/Recommended: Select backup and restore to create a backup of the current installation on the Xperia Ray.

    Select the options to "wipe data/factory reset" and "wipe cache"
    Select "Install zip from sdcard"
    Select Choose the your rom zip from sdcard.
    Select the your rom zip file you placed on the sdcard. You will then need to then confirm that you do wish to flash this file.

    Install the Google Apps package as well

    Optional: Install any additional packages you wish using the same method.

Once the installation has finished, return back to the main menu, and select the reboot system now.