You can go through each piece of information in your phone and delete it to reset your SIM card. A SIM card stands for subscriber identity module and stores most of the information that goes through your phone. You can buy a SIM card reader that will allow you to clear the memory. This reader is small and plugs into your computer's USB port.
Go to your phone's contacts list. Click on any entry in your contacts list and open the "Options" menu. In the "Options" menu, select the "Delete" option. Go through each entry in your contacts list and delete it. If your contact entries are saved to your phone and not to your SIM card, you don't have to delete them.
Open your phone's "Messages" menu. Go through your text messages and delete each one. Go through your "Outbox" and "Sent Items" folder and delete any messages that may be saved there.
Plug your SIM card reader into your computer and install the software that came with the reader. Some readers are plug-and-play, which means you don't have to install any software for them to work.
Remove the SIM card from your phone. In order to remove the SIM card, take off the back cover and remove the battery. You will see the SIM card snugly fit into the cell phone. Either slide the card out of place or unhook the mechanism holding it in place.
Insert the SIM card into your SIM card reader. You will have to read the directions to know the correct way to insert the card.
Open the reader program on your computer. Follow the directions for your specific reader on how to clear data from your SIM card. Remove all the data you want cleared from your SIM card.