1. Turn your Sony VGN-FW198U laptop over.
2. Find the laptop battery release button lock for your Sony VGN-FW198U laptop.
3. Now that your Sony VGN-FW198U laptop battery is unlocked, find the battery release button down.
4. Holding the laptop battery release button, gently pull your battery away from the laptop.
5. Now that your Sony VGN-FW198U battery is removed, grab your replacement Sony VGN-FW198U battery for installation.
6. Insert the battery into the slot. Push the Sony VGN-FW198U battery towards the laptop and secure it in place.