See also:

Safety belt reminder for the driver's and front passenger seat
The indicator lamp flashes or lights up and a signal sounds. Make sure that the safety belts are positioned correctly. The safety belt reminder is active at speeds above approx. 5 mph/8 km/h ...

Have maintenance carried out
Have vehicles maintained regularly to achieve optimal vehicle economy and operating life. Have the maintenance carried out by your service center. Please also note the BMW Maintenance System ...

Remove attached partsfollowing use
Remove auxiliary mirrors, roof or rear luggage racks which are no longer required following use. Attached parts on the vehicle impair the aerodynamics and increase the fuel consumption. ...