This guide goes with the
To backup your Android ID, so as to not lose it if you are changing it, follow the below steps: Open Titanium Backup (For installation instructions, see the thread linked above). Press the search button on your device, which will give you the below screen: In the box, search "setting", and you will need to click on the "Settings Storage" result, as shown below: Clicking this will give you something like: + Tap on the entry: Tap on "Backup!".
Now, If you need to restore your Android ID, follow the below steps.
Once you have gotten this far, press "Restore Android ID from backup".
You will see something like this, except with a different device name: