1. Determine the type of laptop video port you have, e.g. HDMI, DVI, VGA, etc.
2. Obtain a compatible cable to connect the laptop video port to the external monitor.
3. Find the make and model of the laptop and check for compatible drivers and graphics card updates.
4. Ensure the external monitor is turned on and select the appropriate external source or input.
5. Change the resolution of the external monitor to the desired screen size.
6. Configure the display settings to adjust the size of the image shown on the external monitor.