1. Turn your Sony VGN-FS8900PV laptop over.
2. Find the laptop battery release button lock for your Sony VGN-FS8900PV laptop.
3. Now that your Sony VGN-FS8900PV 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-FS8900PV battery is removed, grab your replacement Sony VGN-FS8900PV battery for installation.
6. Insert the battery into the slot. Push the Sony VGN-FS8900PV battery towards the laptop and secure it in place.