Power off the Raspberry Pi
Identify the touchscreen type
Connect the touchscreen via HDMI, DSI, or USB as required
Connect the touchscreen power cable if needed
Connect the touchscreen ribbon cable securely if using DSI
Connect the touchscreen USB cable for touch input if required
Attach the Raspberry Pi to a compatible power supply
Power on the Raspberry Pi
Open the Raspberry Pi desktop or terminal
Check display detection in the system settings
Install any required touchscreen drivers
Calibrate the touchscreen if necessary
Reboot the Raspberry Pi if the screen does not respond
Adjust display orientation if needed