Start by going to the settings screen by pressing the M (Menu) button. Once you are in the Settings screen, cursor down to the FCWS DETECT and LDWS DETECT items.  Enable these by setting them to ON.
Set FCWS SENSITIVITY to Medium initially.
Set LDWS MINIMUM SPEED (MPH) to 30 MPH.  You can adjust this value later, depending on your needs.  Setting this to a higher number ensures that you won't get warnings at low speeds.
Calibration is a key step to ensure that LDWS and FCWS work as expected.  Cursor down till you see ADAS CALIBRATION.  Set this value to YES.
Now press the M button to go back to the viewfinder screen.  You will see two horizontal lines: a purple line and a red Line.
You have to align the Purple line to the Horizon (where the scenery ahead meets the sky).  You have to align the Red Line to front of the car (where the car appears to end and the road begins).
To adjust the lines, do NOT move your camera.  Instead hold the camera firmly, and press the Up/Left or Down/Right keys.  This will move the currently selected line (say, the Purple line).  
To select the other line, press the CAPTURE PHOTO / DELETE button.  Once again, press the Up/Left or Down/Right keys to move this line (say, the Red line).  
Press the OK/Record Video button to accept the calibration.  You are done!