1. Turn your HP CQ61z-300 laptop over.
2. Find the laptop battery release button lock for your HP CQ61z-300 laptop.
3. Now that your HP CQ61z-300 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 HP CQ61z-300 battery is removed, grab your replacement HP CQ61z-300 battery for installation.
6. Insert the battery into the slot. Push the HP CQ61z-300 battery towards the laptop and secure it in place.