Orange is a GSM cellular provider based in the United Kingdom. In addition to traditional postpaid plans, Orange also offers pay-as-you-go wireless options and sends out free SIM cards to those who bring their own unlocked mobile phone to the service. If you choose to order a free SIM card, you have to activate it with Orange before your phone can use the cellular network. Luckily, Orange has made SIM card activation a very simple process.
Locate the SIM card number for your Orange SIM card. This number will either be located on the card itself or in the documentation that came with the card.
Open a web browser and visit Orange's SIM activation website (see Resources).
Enter your SIM card number into the "SIM number" field and click "Next."
Follow the rest of the instructions to register your account and add minutes to your phone.