1. Turn your Toshiba L355D laptop over.
2. Find the laptop battery release button lock for your Toshiba L355D laptop.
3. Now that your Toshiba L355D 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 Toshiba L355D battery is removed, grab your replacement Toshiba L355D battery for installation.
6. Insert the battery into the slot. Push the Toshiba L355D battery towards the laptop and secure it in place.