GSM (Global System for Mobile Communications) phones are not easy to clone. Unlike other popular phone formats, they do not contain extractable data on the phone's preferences or internal data. Cloning methods that work on other types of phones fail on GSM phones. Cloning a GSM is possible, though, through the SIM card. This will clone all the data concerning messages, photos, and contacts.
Purchase a SIM card duplicator if you do not have one already. These small devices can read and write to GSM phone SIM cards. You can purchase them for most hardware stores, often for less than £13.
Remove the SIM card from your GSM phone by taking out the battery and sliding the card out from its holder.
Insert the card into the slot on the top of the SIM card duplicator.
Connect the SIM card duplicator to your computer. A window will open after a few seconds.
Click "Locate IMEI Number" (or similar). This number identifies your specific card.
Select "Extract Authentication Key" (or similar). The program will need to connect to the Internet to find the unique key that matches your IMEI.
Remove the SIM card when prompted to do so and insert the new SIM card.
Click "Write Card" (or similar). This will clone the GSM data from the first card onto the new SIM card. Now both cards contain the same GSM data, with the exception of the phone preferences.