1. On the bottom of your Gateway M150 laptop, find the hard drive door to access the hard drive.
2. Remove the Screws.
3. In this step, you will either need to pry out your Gateway M150 hard drive caddy, or simply remove the door.
4. Once the Gateway M150 hard drive is removed the laptop, you need to remove the hard drive caddy. There are usually four screws to remove from the caddy.
5. Simply Insert the new hard drive into the caddy. Place the screws back in. Install your new Gateway M150 hard drive.