Follow the instruction from Using QGroundControl via Wi-Fi.
SSH into the raspberry pi, change the parameter gcs_bridge in ~/catkin_ws/src/clover/clover/launch/clover.launch to tcp.
Restart the clover service by sudo systemctl restart clover.
Get to QGroundControl program, choose the Application settings → Comm Links → Add.
Change the random Name.
Type to TCP.
Host Address is your raspi ip address.
TCP Port to 5760.
Press OK. Then click Connect.
Follow Sensor Calibration instruction. If the flight controller is COEX Pix, specify ROTATION_ROLL_180_YAW_90.
When calibrating the Compass, please hold still in specific orientation. The status should change from Incomplete to Rotate. Then start to rotate your drone until Rotate to Complete.
While calibrating other sensors, they only require to hold still the drone in specific orientation.
Reboot via Vehicle Setup → Parameters → Tools → Reboot.