See also:

Close the windows and glass sunroof
Driving with the glass sunroof and windows open results in increased air resistance and raises fuel consumption. ...

Jump-starting
If the car's own battery is flat, your BMW's engine can be started by connecting two jumper cables to another vehicle's battery. You can also use the same method to help start another ...

Look well ahead when driving
Avoid unnecessary acceleration and braking. By maintaining a suitable distance to the vehicle driving ahead of you. Driving smoothly and looking ahead reduces fuel consumption. ...