Formatting a memory card inside the camera in which it will be used is a very good means of maintaining a card's full capabilities. While the exact formatting procedure and menu display may differ between cameras, the following ten-step guidelines will be able to perform the task for most cameras.
Turn the camera off and insert the memory card you wish to format into the camera's memory card slot.
Turn the camera on and verify that the battery is well charged. If necessary, recharge the battery.
Verify that all valuable information on the card has been backed-up. If not, transfer the imaging data you want to keep to another storage medium.
Press the Menu button to activate the Menu display on the rear screen.
Navigate to the "Format" or "Format Memory Card" item in the menu, which is often found within the "Setup" screen.
Select/highlight the "Format" or "Format Memory Card" item and then press "OK".
In case a confirmation message appears, confirm your intend of formatting the card by selecting "Yes" and pressing "OK".
Wait until the formatting process, which for large memory cards can take several minutes, is completed. The end of the formatting procedure will normally be indicated on the rear screen.
Turn off the camera once the process is completed.
Congratulations, you now have a clean and well formatted memory card!
In case this process does not apply to your camera, please consult the camera's instruction manual or contact the manufacturer's technical support staff for further guidance.